In this article, we will look at the principles of operation of sensors. optical mice, shed light on the history of their technological development, and also debunk some of the myths associated with optical "rodents".

Who made you...

Optical mice familiar to us today trace their pedigree since 1999, when the first copies of such manipulators from Microsoft appeared on mass sale, and after a while from other manufacturers. Before the advent of these mice, and for a long time after that, most mass computer "rodents" were optomechanical (the movements of the manipulator were tracked by an optical system associated with the mechanical part - two rollers responsible for tracking the movement of the mouse along the x and y axes; these rollers, in in turn, rotated from the ball rolling when the user moved the mouse). Although there were also purely optical models of mice that required a special rug for their work. However, such devices were not often encountered, and the very idea of ​​​​development of such manipulators gradually came to naught.

The “view” of mass optical mice familiar to us today, based on the general principles of operation, was “bred” in the research laboratories of the world famous corporation Hewlett-Packard. More precisely, in its division of Agilent Technologies, which only relatively recently completely separated into a separate company in the structure of HP Corporation. To date, Agilent Technologies, Inc. - a monopolist in the market of optical sensors for mice, no other companies develop such sensors, no matter what anyone tells you about the exclusive IntelliEye or MX Optical Engine technologies. However, the enterprising Chinese have already learned how to “clone” Agilent Technologies sensors, so when you buy an inexpensive optical mouse, you may well become the owner of a “left” sensor.

Where the visible differences in the operation of manipulators come from, we will find out a little later, but for now, let's start considering the basic principles of the operation of optical mice, or rather their movement tracking systems.

How do computer mice "see"

In this section, we will study the basic principles of operation of optical motion tracking systems, which are used in modern mouse-type manipulators.

So, the "vision" of the optical computer mouse is due to the following process. With the help of an LED, and a system of lenses focusing its light, a surface area is highlighted under the mouse. The light reflected from this surface, in turn, is collected by another lens and enters the receiving sensor of the microcircuit - the image processor. This chip, in turn, takes pictures of the surface under the mouse at a high frequency (kHz). Moreover, the microcircuit (let's call it an optical sensor) not only takes pictures, but also processes them itself, since it contains two key parts: the Image Acquisition System (IAS) image acquisition system and an integrated DSP image processor.

Based on the analysis of a series of successive shots (which are a square matrix of pixels of different brightness), the integrated DSP processor calculates the resulting indicators indicating the direction of mouse movement along the x and y axes, and transmits the results of its work outside via the serial port.

If we look at the block diagram of one of the optical sensors, we will see that the microcircuit consists of several blocks, namely:

• the main block is, of course, ImageProcessor- image processor (DSP) with built-in light signal receiver (IAS);
• Voltage Regulator And Power Control- a voltage adjustment and power consumption control unit (power is supplied to this unit and an additional external voltage filter is connected to it);
• Oscillator- an external signal is supplied to this block of the chip from a master crystal oscillator, the frequency of the incoming signal is about a couple of tens of MHz;
• Led Control- this is a LED control unit, with which the surface under the mouse is highlighted;
• Serial port- a block that transmits data about the direction of mouse movement outside the chip.

We will consider some details of the operation of the optical sensor chip a little later, when we get to the most advanced of modern sensors, but for now let's return to the basic principles of operation of optical systems for tracking the movement of manipulators.

It should be clarified that the optical sensor chip does not transmit information about mouse movement directly to the computer via the Serial Port. Data is sent to another controller chip installed in the mouse. This second "master" chip in the device is responsible for responding to mouse clicks, scroll wheel rotation, etc. This chip, among other things, already directly transmits information about the direction of mouse movement to the PC, converting the data coming from the optical sensor into signals transmitted via PS / 2 or USB interfaces. And already the computer, using the mouse driver, based on the information received via these interfaces, moves the cursor-pointer across the monitor screen.

It is precisely because of the presence of this “second” controller chip, or rather due to different types such microcircuits, already the first models of optical mice differed quite noticeably among themselves. If I can’t speak too badly about expensive devices from Microsoft and Logitech (although they were not at all “sinless”), then the mass of inexpensive manipulators that appeared after them did not behave quite adequately. When moving these mice on ordinary rugs, the cursors on the screen made strange somersaults, jumped almost to the floor of the desktop, and sometimes ... sometimes they even went on an independent journey across the screen when the user did not touch the mouse at all. It even got to the point that the mouse could easily bring the computer out of standby mode, erroneously registering the movement, when no one actually touched the manipulator.

By the way, if you are still struggling with a similar problem, then it is solved in one fell swoop like this: select My Computer\u003e Properties\u003e Hardware\u003e Device Manager\u003e select the installed mouse\u003e go to its "Properties"\u003e in the window that appears, go to the tab "Management power supply" and uncheck the box "Allow the device to bring the computer out of standby mode" (Fig. 4). After that, the mouse will no longer be able to wake the computer from standby under any pretext, even if you kick it with your feet :)

So, the reason for such a striking difference in the behavior of optical mice was not at all in the "bad" or "good" installed sensors, as many still think. Believe me, this is nothing more than a myth. Or fantasy, if you like it that way :) Mice behaving in completely different ways often had exactly the same optical sensor chips installed (fortunately, there were not so many models of these chips, as we will see below). However, thanks to the imperfect controller chips installed in optical mice, we had the opportunity to strongly scold the first generations of optical rodents.

However, we have digressed somewhat from the topic. We return. In general, the mouse optical tracking system, in addition to the sensor chip, includes several more basic elements. The design includes a holder (Clip) in which an LED is installed and the sensor chip itself (Sensor). This system of elements is mounted on a printed circuit board (PCB), between which and the bottom surface of the mouse (Base Plate) a plastic element (Lens) is fixed, containing two lenses (the purpose of which was described above).

When assembled, the optical tracking element looks like shown above. The scheme of operation of the optics of this system is presented below.

The optimal distance from the Lens element to the reflective surface under the mouse should be between 2.3 and 2.5 mm. These are the sensor manufacturer's recommendations. Here is the first reason why optical mice feel bad “crawling” on plexiglass on the table, all kinds of “translucent” rugs, etc. And you should not glue “thick” legs on optical mice when the old ones fall off or are erased. The mouse, due to excessive “elevation” above the surface, can fall into a state of stupor, when it becomes quite problematic to “stir up” the cursor after the mouse is at rest. These are not theoretical fabrications, this is personal experience :)

By the way, about the problem of durability of optical mice. I remember that some of their manufacturers claimed that, they say, "they will last forever." Yes, the reliability of the optical tracking system is high; it cannot be compared with the optomechanical one. At the same time, there are many purely mechanical elements in optical mice that are subject to wear in the same way as under the dominance of the good old “optomechanics”. For example, the legs of my old optical mouse were worn out and fell off, the scroll wheel broke (twice, the last time irrevocably :(), the wire in the connecting cable frayed, the cover of the case peeled off the manipulator ... but the optical sensor works fine, as if nothing Based on this, we can safely state that rumors about the allegedly impressive durability of optical mice have not been confirmed in practice. And why, pray tell, optical mice "live" for too long? After all, new, more "Perfect models created on a new element base. They are obviously more perfect and more convenient to use. Progress, you know, is a continuous thing. Let's see what it was like in the field of evolution of the optical sensors we are interested in, let's see now."

From the history of mouse vision

Development engineers at Agilent Technologies, Inc. they do not eat their bread in vain. Over the past five years, the company's optical sensors have undergone significant technological improvements and their latest models have very impressive characteristics.

But let's talk about everything in order. Chips were the first mass-produced optical sensors. HDNS-2000(Fig. 8). These sensors had a resolution of 400 cpi (counts per inch), i.e. dots (pixels) per inch, and were designed for a maximum mouse movement speed of 12 inches / s (about 30 cm / s) with an optical sensor frame rate of 1500 frames in a second. Permissible (with preservation stable operation sensor) acceleration when moving the mouse "in a jerk" for the HDNS-2000 chip - no more than 0.15 g (about 1.5 m/s 2).

Then optical sensor chips appeared on the market. ADNS-2610 And ADNS-2620. The optical sensor ADNS-2620 already supported a programmable frequency of "shooting" the surface under the mouse, with a frequency of 1500 or 2300 shots / s. Each picture was taken with a resolution of 18x18 pixels. For the sensor, the maximum operating speed of movement was still limited to 12 inches per second, but the limit on permissible acceleration increased to 0.25 g, with a surface “photographing” rate of 1500 frames / s. This chip (ADNS-2620) also had only 8 legs, which made it possible to significantly reduce its size compared to the ADNS-2610 chip (16 pins), which looks similar to the HDNS-2000. At Agilent Technologies, Inc. set out to "minimize" their chips, wanting to make the latter more compact, more economical in power consumption, and therefore more convenient for installation in "mobile" and wireless manipulators.

The ADNS-2610 chip, although it was a “large” analogue of the 2620, was deprived of support for the “advanced” mode of 2300 shots / s. In addition, this option required 5V power, while the ADNS-2620 chip cost only 3.3V.

Chip coming soon ADNS-2051 was a much more powerful solution than the HDNS-2000 or ADNS-2610 chips, although outwardly (packaging) it was also similar to them. This sensor already made it possible to programmatically control the "resolution" of the optical sensor, changing it from 400 to 800 cpi. The variant of the microcircuit also allowed adjusting the frequency of surface shots, and it allowed changing it in a very wide range: 500, 1000,1500, 2000 or 2300 shots/s. But the size of these very pictures was only 16x16 pixels. At 1500 shots/s, the maximum allowable acceleration of the mouse during the "jerk" was still 0.15 g, the maximum possible movement speed was 14 inches/s (i.e., 35.5 cm/s). This chip was designed for a supply voltage of 5 V.

Sensor ADNS-2030 designed for wireless devices, and therefore had low power consumption, requiring only 3.3 V power. The chip also supported energy-saving functions, such as the function to reduce power consumption when the mouse is at rest (power conservation mode during times of no movement), switch to sleep mode, including when the mouse is connected via USB interface, etc. The mouse, however, could also work in a non-power-saving mode: the value "1" in the Sleep bit of one of the chip registers made the sensor "always awake", and the default value "0" corresponded to the operating mode of the microcircuit, when after one second, if the mouse did not move (more precisely, after receiving 1500 completely identical surface shots), the sensor, along with the mouse, went into power saving mode. As for the other key characteristics of the sensor, they did not differ from those of the ADNS-2051: the same 16-pin package, movement speed up to 14 inches / s with a maximum acceleration of 0.15 g, programmable resolution of 400 and 800 cpi, respectively, snapshot rates could be exactly the same as the above-considered version of the microcircuit.

These were the first optical sensors. Unfortunately, they were characterized by shortcomings. A big problem that occurred when moving an optical mouse over surfaces, especially with a repeating small pattern, was that the image processor sometimes confused separate similar areas of a monochrome image received by the sensor and incorrectly determined the direction of mouse movement.

As a result, the cursor on the screen did not move as required. The pointer on the screen even became capable of impromptu:) - of unpredictable movements in an arbitrary direction. In addition, it is easy to guess that if the mouse was moved too fast, the sensor could generally lose any “link” between several subsequent surface shots. Which gave rise to another problem: the cursor, when moving the mouse too sharply, either twitched in one place, or “supernatural” phenomena occurred in general :) phenomena, for example, with the rapid rotation of the world around in toys. It was quite clear that for the human hand, the limitations of 12-14 inches / s in terms of the maximum speed of moving the mouse are clearly not enough. There was also no doubt that 0.24 s (almost a quarter of a second), allotted for accelerating the mouse from 0 to 35.5 cm / s (14 inches / s - the maximum speed) is a very long period of time, a person is able to move the brush much faster. And therefore, with sharp mouse movements in dynamic gaming applications with an optical manipulator, it can be hard ...

Agilent Technologies understood this too. The developers realized that the characteristics of the sensors needed to be radically improved. In their research, they adhered to a simple but correct axiom: the more pictures per second the sensor takes, the less likely it is to lose the “trace” of mouse movement when the computer user makes sudden movements :)

Although, as we can see from the above, optical sensors have evolved, new solutions are constantly being released, however, development in this area can be safely called “very gradual”. By and large, there were no cardinal changes in the properties of the sensors. But technological progress in any field is sometimes characterized by sharp jumps. There was such a “breakthrough” in the field of creating optical sensors for mice. The advent of the ADNS-3060 optical sensor can be considered truly revolutionary!

Best of

Optical sensor ADNS-3060, compared to its "ancestors", has a truly impressive set of characteristics. The use of this chip, packaged in a 20-pin package, provides optical mice with never-before-seen possibilities. The permissible maximum moving speed of the manipulator has increased to 40 inches / s (that is, almost 3 times!), i.e. reached the "sign" speed of 1 m/s. This is already very good - it is unlikely that at least one user moves the mouse at a speed exceeding this limit so often that he constantly feels discomfort from using the optical manipulator, including gaming applications. The allowable acceleration, however, has increased, frighteningly, by a hundred times (!), and has reached a value of 15 g (almost 150 m/s 2). Now, the user is given 7 hundredths of a second to accelerate the mouse from 0 to the maximum 1 m / s - I think that now very few will be able to exceed this limitation, and even then, probably in dreams :) The programmable speed of taking surface images with an optical sensor in the new chip model exceeds 6400 fps, i.e. "beats" the previous "record" almost three times. Moreover, the ADNS-3060 chip can itself adjust the image repetition rate to achieve the most optimal operating parameters, depending on the surface over which the mouse moves. The "resolution" of the optical sensor can still be 400 or 800 cpi. Let's use the example of the ADNS-3060 microcircuit to consider the general principles of operation of optical sensor chips.

The general scheme for analyzing mouse movements has not changed compared to earlier models - microimages of the surface under the mouse obtained by the IAS sensor unit are then processed by the DSP (processor) integrated in the same chip, which determines the direction and distance of the movement of the manipulator. The DSP calculates the relative x and y offset values ​​relative to the mouse's home position. Then the external mouse controller chip (what we need it for, we said earlier) reads information about the movement of the manipulator from the serial port of the optical sensor chip. Then this external controller translates the received data about the direction and speed of mouse movement into signals transmitted via standard PS / 2 or USB interfaces, which are already coming from it to the computer.

But let's delve a little deeper into the features of the sensor. The block diagram of the ADNS-3060 chip is presented above. As you can see, its structure has not fundamentally changed compared to its distant "ancestors". 3.3 Power is supplied to the sensor through the Voltage Regulator And Power Control block, the same block is assigned the voltage filtering function, for which connection to an external capacitor is used. The signal coming from the external quartz resonator to the Oscillator block (the nominal frequency of which is 24 MHz, lower-frequency master oscillators were used for previous microcircuit models) serves to synchronize all computational processes occurring inside the optical sensor microcircuit. For example, the frequency of snapshots of an optical sensor is tied to the frequency of this external generator (by the way, the latter is not subject to very strict restrictions on permissible deviations from the nominal frequency - up to +/- 1 MHz). Depending on the value entered at a certain address (register) of the chip memory, the following operating frequencies for taking pictures by the ADNS-3060 sensor are possible.

Register value, hexadecimal	Decimal value	Sensor snapshot rate, fps
OE7E	3710	6469
12C0	4800	5000
1F40	8000	3000
2EE0	12000	2000
3E80	16000	1500
BB80	48000	500

As you might guess, based on the data in the table, determining the frequency of sensor snapshots is carried out according to a simple formula: Frame rate \u003d (Generator master frequency (24 MHz) / Frame rate register value).

The surface images (frames) taken by the ADNS-3060 sensor have a resolution of 30x30 and represent the same matrix of pixels, the color of each of which is encoded in 8 bits, i.e. one byte (corresponding to 256 shades of gray for each pixel). Thus, each frame (frame) entering the DSP processor is a sequence of 900 bytes of data. But the "cunning" processor does not process these 900 bytes of a frame immediately upon arrival, it waits until 1536 bytes of pixel information are accumulated in the corresponding buffer (memory) (that is, information about another 2/3 of the next frame is added). And only after that, the chip starts to analyze information about the movement of the manipulator by comparing changes in successive surface images.

With a resolution of 400 or 800 pixels per inch, they are indicated in the RES bit of the microcontroller memory registers. A zero value of this bit corresponds to 400 cpi, and a logical one in RES puts the sensor in 800 cpi mode.

After the integrated DSP processor processes the image data, it calculates the relative offset values ​​of the manipulator along the X and Y axes, entering specific data about this into the memory of the ADNS-3060 chip. In turn, the microcircuit of the external controller (mouse) through the Serial Port can "scoop" this information from the memory of the optical sensor with a frequency of about once per millisecond. Note that only an external microcontroller can initiate the transfer of such data, the optical sensor itself will never initiate such a transfer. Therefore, the question of the efficiency (frequency) of tracking the movement of the mouse largely lies on the "shoulders" of the external controller chip. Data from the optical sensor is transmitted in 56-bit packets.

Well, the Led Control block, which the sensor is equipped with, is responsible for controlling the backlight diode - by changing the value of bit 6 (LED_MODE) at address 0x0a, the optosensor microprocessor can switch the LED to two operating modes: logical "0" corresponds to the state "diode is always on", logical "1" puts the diode in "on only when needed" mode. This is important, say, when working with wireless mice, as it allows you to save the charge of their autonomous power sources. In addition, the diode itself can have several brightness modes.

That, in fact, is all with the basic principles of the optical sensor. What else can be added? The recommended operating temperature of the ADNS-3060 chip, as well as all other chips of this kind, is from 0 0С to +40 0С. Although Agilent Technologies guarantees the preservation of the working properties of its chips in the temperature range from -40 to +85 °С.

Laser future?

Recently, the web was filled with laudatory articles about the Logitech MX1000 Laser Cordless Mouse, which used an infrared laser to illuminate the surface under the mouse. It promised almost a revolution in the field of optical mice. Alas, having personally used this mouse, I was convinced that the revolution did not happen. But it's not about that.

I have not disassembled the Logitech MX1000 mouse (did not have the opportunity), but I am sure that our old friend, the ADNS-3060 sensor, is behind the "new revolutionary laser technology". For, according to the information I have, the characteristics of the sensor of this mouse are no different from those of, say, the Logitech MX510 model. All the "hype" arose around the statement on the Logitech website that using a laser optical tracking system, twenty times (!) More details are revealed than using LED technology. On this basis, even some respected sites have published photographs of some surfaces, they say, as they see their ordinary LED and laser mice :)

Of course, these photos (and thanks for that) were not the multi-colored bright flowers with which they tried to convince us on the Logitech website of the superiority of the laser illumination of the optical tracking system. No, of course, optical mice did not “see” anything similar to the given color photographs with varying degrees of detail - the sensors still “photograph” no more than a square matrix of gray pixels that differ only in different brightness (processing information about the extended color the palette of pixels would be an exorbitant burden on the DSP).

Let's think, to get a 20 times more detailed picture, you need, sorry for the tautology, twenty times more details, which can only be conveyed by additional image pixels, and nothing else. It is known that the Logitech MX 1000 Laser Cordless Mouse takes pictures of 30x30 pixels and has a maximum resolution of 800 cpi. Consequently, there can be no question of any twenty-fold increase in the detailing of images. Where did the dog fumble :), and are such statements generally unfounded? Let's try to figure out what caused the appearance of this kind of information.

As you know, a laser emits a narrowly directed (with a small divergence) beam of light. Therefore, the illumination of the surface under the mouse with a laser is much better than with an LED. The laser operating in the infrared range was chosen, probably in order not to dazzle the eyes by the possible reflection of light from under the mouse in the visible spectrum. The fact that the optical sensor works normally in the infrared range should not be surprising - from the red range of the spectrum, in which most LED optical mice work, to the infrared - "at hand", and it is unlikely that the transition to a new optical range was difficult for the sensor. For example, the Logitech MediaPlay manipulator uses an LED, but also provides infrared illumination. Current sensors work without problems even with blue light (there are manipulators with such illumination), so the spectrum of the illumination area is not a problem for sensors. So, due to the stronger illumination of the surface under the mouse, we can assume that the difference between places that absorb radiation (dark) and reflect rays (light) will be more significant than when using a conventional LED - i.e. the image will be more contrast.

Indeed, if we look at real images of the surface taken by a conventional LED optical system and a system using a laser, we will see that the "laser" version is much more contrast - the differences between the dark and bright areas of the image are more significant. Of course, this can significantly facilitate the work of the optical sensor and, perhaps, the future belongs to mice with a laser illumination system. But it is hardly possible to call such "laser" images twenty times more detailed. So this is another "newborn" myth.

What will be the optical sensors of the near future? It's hard to say. They will probably switch to laser illumination, and there are already rumors on the Web about a sensor being developed with a “resolution” of 1600 cpi. We can only wait.

When buying a computer, many users pay attention only to the choice of the main and most expensive components - a processor, motherboard, video cards, etc.

As for the choice peripherals( , mouse), then many characteristics are overlooked here. Often the user takes what is included with system block, and then wonders why the mouse quickly fails (or it is simply uncomfortable to hold in your hand).

In this article, we will look at the main characteristics of a computer mouse that you should consider when buying.

1 Size and shape

Most of all computer operations are performed using the mouse. Consequently, the user almost constantly holds the mouse in his hand and moves it on the table or on the rug. This explains the need to choose exactly the device that, in its shape and size, is ideal for the shape and size of the palm. Otherwise, holding the mouse will not be very comfortable, you will get tired faster and get less pleasure from work.

I even know people whose hand hurt so much when working with an uncomfortable mouse for a long time, that for a while they involuntarily became left-handed. When the hand began to break, as they say, the mouse moved to the left, to the left hand, the mouse buttons were rearranged for the left hand, and thus it was possible to calm the right hand. This is very inconvenient, unless you are a real left-hander, and work on the computer slows down a lot.

Therefore, before buying, be sure to hold the mouse in your hand and estimate how convenient it is to work with it, how comfortable it is to hold it in your hand (in the right hand for right-handers and in the left hand for left-handers).

2 Type (type) of a computer mouse

According to their type, mice are divided into

• mechanical,
• optical and
• remote.

Depending on the type, let's see what a computer mouse looks like.

Mechanical manipulators use a special ball that rotates as the device moves across a flat surface.

Rice. 1 mechanical mouse

Optical mouse manipulators use an optical pointer that reads changes in the position of the mouse relative to the plane along which the mouse is moving.

Rice. 2 optical mouse computer USB connection

Remote mice work on the same principle as optical mice, but they do not have a wired connection to the computer.

Rice. 3 Remote mouse

For remote mice, the signal from the manipulator is transmitted wirelessly remotely, while the mice themselves are powered by a battery or from an accumulator.

Mechanical mice are now obsolete. Almost no one uses them because of the relatively low sensitivity and frequent failures. They quickly accumulate dust and dirt, which interfere with the normal operation of the rotating ball and reading sensors. It makes no sense to buy such manipulators, even if they are attractive in price.

Optical mice are the most common (due to ease of use, reliability and durability).

Remote mice are also used quite often, but have a number of disadvantages. For instance,

• possible problems with sensitivity (including due to the lack of wires),
• the need for periodic replacement of batteries,
• battery charge control, if used.

However, such remote mice can be useful for those who work at a distance from the computer. For example, in the case of using a computer as a TV, it is more convenient to switch TV channels remotely, being at a distance, sitting, as they say, on the couch, for which a remote mouse can be oh so useful!

Remote mice are also convenient for those who make presentations using a computer, but do not have the opportunity to work with professional equipment. Then a computer (more often not even a computer, but a laptop) is used as a screen for demonstration, and a remote mouse allows you to switch presentation slides remotely (for example, while standing during a speech).

3 Connector for connection

Any mice, even remote ones, must be connected to the computer through ports. Wired mice have a corresponding connector at the end of the wire. Wireless mice have a special device like a small flash drive, which is also connected to the PC port and serves as a receiver for signals from the remote mouse.

Rice. 4 PC/2 ports

The mouse can be connected to the computer

• to the PC/2 port (fig. 4 – round port),
• as well as to the USB port (Fig. 2).

At the same time, USB mice are rapidly replacing mice with a PC / 2 cable from the market. There are several reasons for this:

• firstly, a better connection;
• secondly, the prevalence of USB connectors on almost all modern PCs.

It also happens that there are not so many USB ports on the computer, and they may not be enough to connect a mouse. Rarely, but this can happen. Then they come to the rescue - these are devices that allow you to make 2, 4 or more USB ports from one USB port. This increases the cost of buying a mouse, since you have to buy a splitter in addition to it, but it solves the problem of a lack of ports. Fortunately, the lack of USB is an extremely rare situation, in ordinary PCs (if it is not “exotic”) there are always enough USB ports to connect a mouse.

For those who do not want to part with the familiar and become “native” mouse with a PS-2 connector when switching to a PC where there are no longer PS-2 ports, the industry (unfortunately, not quite native, but rather Chinese!) Offers PS adapters -2 - USB. Again, this is a rare occurrence, it is easier to change the mouse to USB than to look for, buy, pay for an adapter. However, for those who wish, we can offer such a somewhat exotic option for connecting a mouse to a computer.

4 Sensitivity

This indicator is measured in dpi (dots per inch). The higher the sensitivity of the computer mouse, the more accurately you can move the mouse cursor around the working space (on the screen) of the monitor.

Let's explain. We are talking about the accuracy with which you can place the mouse cursor at one point or another on the screen. The higher the sensitivity, that is, the more dots per inch, the more accurately you can set the mouse cursor at the desired point on the screen.

Let me remind you that an inch is 2.54 cm. And we use this length measurement system because we are not the progenitors of computer technology, and therefore we use someone else's system of measures and weights.

High sensitivity, in fact, is not only a blessing. High sensitivity, on the contrary, can cause problems, difficulties in working with the mouse. High sensitivity is important for those who work with high-resolution computer graphics, for computer designers, for designers and similar professions that require drawing or drafting using a PC. High sensitivity can be useful for "gamers", fans of computer games, where the accuracy of hitting certain fields on the monitor screen is important.

Otherwise, ordinary PC users can get by with mouse manipulators with relatively low accuracy. Why high accuracy if you are engaged, for example, only in editing texts? You can easily get the mouse to the desired line, to the desired character of the text, as they say, “without aiming” and you won’t miss!

The sensitivity of many mechanical mice ranges from 400-500 dpi. However, as noted earlier, this type of manipulators is already in the past. In optical models, the dpi value can reach 800-1000.

The cost of a particular mouse model directly depends on the sensitivity. When buying a mouse with high sensitivity, the PC user additionally pays for this feature. This is another argument in favor of choosing mice that are not too sensitive. Why overpay if high sensitivity is not needed for normal PC work?!

5 Number of buttons

A standard mouse has only three controls - the right and left buttons, as well as the wheel. The mouse wheel is not only the now familiar scrolling tool, but also serves as the third mouse button. You can press the wheel like a button, click it. This allows, for example, opening browser windows in new tabs (see ).

Working with the buttons and with the mouse wheel should be pleasant and comfortable, otherwise such a mouse may annoy the PC user. For example, the buttons (both right and left) can be too tight, pressed with quite a lot of effort. This is not convenient for everyone, and during prolonged work, you can simply get tired of pressing the buttons, which sometimes leads to painful and unpleasant sensations.

Mouse buttons can be pressed quietly, almost silently, or they can click loudly. This is also, as they say, an amateur, someone likes it louder, with a click, and someone prefers silence.

The buttons can be pressed without play, without free play, and in some cases the play can be so great that there is a feeling that the button itself moves a little, sways. Buttons with backlash can be annoying, on the other hand, someone may like them. As they say, for an amateur. You have to try it with your own hands and choose.

Also the mouse wheel. It can spin easily, or it can “slow down” and require additional effort. Here too - as you like.

Pressing the wheel may be easy, or it may require some exercise of the index finger. It is especially annoying if the wheel is pressed without a click, when it is not very possible to feel whether the pressing has happened or not. In this case, pressing and scrolling the wheel becomes akin to a roulette wheel, either pan or go! Not very convenient, such a mouse is more for thrill-seekers.

It is better for an ordinary inexperienced PC user to have a mouse, where everything is simple and clear:

• here they are, left and right mouse clicks,
• here it is, scrolling the wheel up and down (attention, sometimes the wheel turns well only up or down in one direction, and sticks in the other, and this should also be checked when buying!).
• And here they are, clear and understandable clicks with the wheel, that is, clicks with the third mouse button.

Everything is simple, reliable, practical.

For ordinary three-button mice, as a rule, no additional drivers are needed, they are already included operating systems PC.

Rice. 5 Mouse with many buttons

In more expensive and advanced models, there may be 4, 5, 6 or more buttons. When installing drivers for such mice, you can "hang" a specific action (or a sequence of actions at once) on each button. This can be very handy when working in some special applications or in computer games. Otherwise, these extra buttons are not needed, it is better not to overpay manufacturers for them, and limit yourself to standard manipulators, two-button mice with a wheel (it is also the third button).

6 Other characteristics

This can be, for example, case material, button material, manufacturer, etc. Here you should choose, focusing only on your own preferences. Someone works well with ordinary plastic mice. Someone prefers metal mice. Some people like regular buttons, while others want buttons with finger-shaped notches for a comfortable hand position.

Someone likes mice of any color, and someone prefers only white, only black, yellow, pink, green, and you never know what other colors are!

Personally, for example, I like mice that work on any surface: on the table, on the mouse pad, on the tablecloth, on oilcloth, on fabric.

And there are mice that, even kill yourself, will not work on a light table, for example, or on oilcloth, or on glass, until you put a mouse pad under them or at least a regular sheet of paper. And this too important characteristic mouse, which we will classify as "other characteristics".

Another “other characteristic” is how quickly the mouse collects dust and dirt from the table, and how easily it is cleaned of this dust and dirt. Unfortunately, there are no ideal jobs. Whatever you do, dust and dirt tend to appear again and again, and they settle on the bottom surface of any, even the cheapest, even the most expensive mouse. And here it is important how quickly the mouse becomes inoperable from this, and how easily it can be cleaned of all this. And a dirty mouse can, for example, lose its sensitivity, or start to work “jerks”, which makes it difficult for the mouse cursor to hit certain points on the screen.

Rice. 6 Apple Touch Mouse

For some PC users, an important "other characteristic" may be the manufacturer's name. For example, having an “advanced” laptop from Apple, you might want a mouse from the same manufacturer with touch controls, when you just move your finger, there are no mechanics, nothing is spinning, but the movement of your finger is captured. For the possession of this manipulator will have to pay extra money.

Or you can just hope that a more or less well-known other company will not sell “bad” mice that can quickly fail. And then you may want to buy a mouse from manufacturers such as Logitech, Microsoft, A4 Tech.

Here, to be honest, how lucky. An unsightly mouse a la "made in China", as they say, "noname" (that is, without a name, without an explicit manufacturer, without a well-known manufacturer) can serve faithfully so much that you forget when, where and at what price you bought it . Or maybe a branded mouse to refuse pretty quickly. Although, on average, mice from well-known manufacturers last longer and work better than their Chinese (and not only) competitors.

So, as you can see, mice are not such simple devices. They have many parameters in which they can differ from each other. Mouse selection - important point when choosing a PC. Since we will have to work with the mouse, since we have become users (and to some extent even hostages) of the modern “window technology” of presenting information on the monitor screen and processing it with modern means that personal computers provide us.

Survey

On this topic, you can add:

A computer mouse is a manipulator for controlling a computer. The manipulator received this name for its external resemblance to a natural rodent. Today, it is an integral attribute of a PC and allows you to interact with it most effectively.

Before the advent of operating systems with a graphical interface, the mouse was not so widespread. Computer control was carried out by entering commands through the keyboard, and working on a computer required high qualifications. In principle, you can get by with a graphical interface with one keyboard, but this will require learning the necessary key combinations for control, which is unacceptable for an ordinary user, and the mouse is a very simple device, and it is not difficult to learn how to work with it. The simplest mouse has a pair of buttons and a wheel between them, with the help of which some action is performed when working with a computer. The mouse is connected to the computer using a wire - wired mice, or wirelessly - the so-called wireless mice.

The principle of the mouse.

The basic principle of a computer mouse is to convert movement into a control signal. When you move the mouse over a surface (most often a table), it generates an electronic signal that tells the computer the direction of movement, distance, and speed. And on the monitor screen, the user sees the movement of a special pointer (cursor) in accordance with the movement of the mouse.

Types of computer mice.

For a long time, mechanical mice were used to control the computer, in which a rubberized metal ball was used as a motion sensor.

mechanical mouse

But progress does not stand still today, the most common computer mice are optical And laser, which have higher positioning accuracy.

IN optical mice to convert motion into an electrical signal, a light source (LED) located on the lower surface of the manipulator and a sensor are used. An optical mouse scans the surface on which it moves, converts the scan results and transfers them to a computer.

Optical mouse

IN laser mouse, a laser is used as an optical source, which makes it possible to increase the positioning accuracy. In addition, the laser mouse is unpretentious to the quality of the surface on which it moves.

laser mouse

There are also more complex and expensive manipulators - touch, induction, gyroscopic mice, which have a different principle for converting movement into a control signal.

Hello, dear readers of the blog site. Computer mice or mice, they are called differently, there are a huge number. According to their functional purpose, they can be divided into classes: some are designed for games, others are for ordinary work, and others are for drawing in graphic editors. In this article I will try to talk about the types and design of computer mice.

But for starters, I propose to go back a few decades, just at the time when they came up with this complex device. The first computer mouse appeared back in 1968, and was invented by an American scientist named Douglas Engelbart. The mouse was developed by the American Space Research Agency (NASA), which granted a patent for the invention to Douglas, but at one point lost any interest in developing it. Why - read on.

The world's first mouse was a heavy wooden box with a wire, which, in addition to its weight, was also extremely inconvenient to use. For obvious reasons, they decided to call it "mouse", and a little later they artificially came up with a decoding of this kind of abbreviation. Yep, now the mouse is nothing more than a "Manually Operated User Signal Encoder", that is, a device with which the user can manually encode a signal.

Without exception, all computer mice include a number of components: body, printed circuit board with contacts, mikriks (buttons), scroll wheel(s) - all of them are present in one form or another in any modern mouse. But you are probably tormented by the question - what then distinguishes them from each other (besides the fact that there are gaming, non-gaming, office, etc.), why did they come up with so many different types, see for yourself:

1. Mechanical
2. Optical
3. Laser
4. Trackball mice
5. induction
6. Gyroscopic

The fact is that each of the above types of computer mice appeared at different times and uses different laws of physics. Accordingly, each of them has its own disadvantages and advantages, which will certainly be discussed later in the text. It should be noted that only the first three types will be considered in most detail, the rest will not be so detailed, in view of the fact that they are less popular.

Mechanical mice are traditional ball models, relatively big size requiring constant cleaning of the ball for effective work. Dirt and small particles can get between the rotating ball and the body and need to be cleaned. It won't work without a mat. About 15 years ago it was the only one in the world. I will write about it in the past tense, because it is already a rarity.

At the bottom of the mechanical mouse there was a hole that covered a swivel plastic ring. Under it was a heavy ball. This ball was made of metal and covered with rubber. Under the ball were two plastic rollers and a roller, which pressed the ball against the rollers. When moving the mouse, the ball rotated the roller. Up or down - one roller rotated, to the right or left - the other. Since gravity played a decisive role in such models, such a device did not work in zero gravity, so NASA abandoned it.

If the movement was difficult, both rollers rotated. At the end of each plastic roller, an impeller was installed, like in a mill, only many times smaller. On one side of the impeller was a light source (LED), on the other - a photocell. When moving the mouse, the impeller was spinning, the photocell read the number of light pulses that hit it, and then transmitted this information to the computer.

Since the impeller had many blades, the movement of the pointer on the screen was perceived as smooth. Optical-mechanical mice (they are simply "mechanical") suffered from great inconvenience, the fact is that they had to be disassembled and cleaned periodically. The ball in the process of work dragged any debris into the case, often the rubber surface of the ball became so dirty that the movement rollers simply slipped and the mouse was buggy.

For the same reason, such a mouse simply needed a pad for correct operation, otherwise the ball would slip and get dirty faster.

Optical and laser mice

In optical mice, you do not need to disassemble and clean anything., since they do not have a rotating ball, they work on a different principle. An optical mouse uses an LED sensor. Such a mouse works like a small camera that scans the surface of the table and "takes pictures" of it, the camera manages to take about a thousand of such photos per second, and some models even more.

The data of these images is processed by a special microprocessor on the mouse itself and sends a signal to the computer. The advantages are obvious - such a mouse does not need a pad, it is light in weight and can scan almost any surface. Nearly? Yes, everything except glass and a mirror surface, as well as velvet (velvet absorbs light very strongly).

A laser mouse is very similar to an optical mouse, but its principle of operation differs in that laser instead of LED. This is a more advanced model of an optical mouse, it requires much less power to work, the accuracy of reading data from the working surface is much higher than that of an optical mouse. Here it can work even on glass and mirror surfaces.

In fact, a laser mouse is a kind of optical mouse, since in both cases an LED is used, just in the second case it emits spectrum invisible to the eye.

So, the principle of operation of an optical mouse differs from that of a ball mouse. .

The process starts with a laser or optical (in the case of an optical mouse) diode. The diode emits invisible light, the lens focuses it to a point equal in thickness to a human hair, the beam is reflected from the surface, then the sensor catches this light. The sensor is so precise that it can pick up even small surface irregularities.

The secret is that precisely the irregularities allow the mouse to notice even the slightest movement. The pictures taken by the camera are compared, the microprocessor compares each subsequent picture with the previous one. If the mouse has moved, the difference between the pictures will be marked.

Analyzing these differences, the mouse determines the direction and speed of any movement. If the difference between shots is significant, the cursor moves quickly. But even when stationary, the mouse continues to take pictures.

Trackball mice

Trackball mouse - a device that uses a convex ball - "Trackball". The trackball device is very similar to the device of a mechanical mouse, only the ball in it is on top or on the side. The ball can be rotated, and the device itself remains in place. The ball causes a pair of rollers to rotate. The new trackballs use optical motion sensors.

Not everyone may need a device called "Trackball", in addition, its cost cannot be called low, it seems that the minimum starts from 1400 rubles.

induction mice

Induction models use a special rug that works on the principle graphics tablet. Induction mice have good accuracy and do not need to be properly oriented. An induction mouse can be wireless or inductively powered, in which case it does not require a battery like a conventional wireless mouse.

I have no idea who would need such devices that are expensive and hard to find on the open market. And why, who knows? Maybe there are some advantages over conventional "rodents"?

Today, the mouse is an essential input device for everyone. modern computers. But quite recently things were different. Computers did not have graphic commands and data could only be entered using the keyboard. And when the very first one appeared, you will be surprised to see what evolution this object familiar to everyone has gone through.

Who invented the first computer mouse?

Considered the father of this device. He was one of those scientists who try to bring science even to ordinary people and make progress accessible to everyone. He invented the first computer mice in the early 1960s in his laboratory at Stanford Research Institute (now SRI International). The first prototype was created in 1964, in the patent application for this invention, filed in 1967, it was called "XY Position Indicator for Display System". But the official document numbered 3541541 was received only in 1970.

But is everything so simple?

It would seem that everyone knows who created the first computer mouse. But trackball (ball drive) technology was first used much earlier by the Canadian Navy. Back then, in 1952, the mouse was just a bowling ball attached to a complex hardware system that could sense the movement of the ball and mimic its movement on a screen. But the world found out about it only years later - after all, it was a secret military invention that was never patented or mass-produced. After 11 years, it was already known, but D. Engelbart recognized it as ineffective. At that moment, he did not yet know how to connect his vision of the mouse and this device.

How did the idea come about?

The main ideas about the invention first came to D. Engelbart in 1961, when he was at a conference on computer graphics and pondered the problem of increasing the efficiency of interactive computing. It occurred to him that by using two small wheels that move across the tabletop (one wheel rotates horizontally and the other vertically), the computer can track combinations of their rotation and move the cursor on the display accordingly. To some extent, the principle of operation is similar to a planimeter - a tool used by engineers and geographers to measure distances on a map or drawing, etc. Then the scientist wrote down this idea in his notebook for future reference.

Step into the Future

A little over a year later, D. Engelbart received a grant from the institute to launch his research initiative called "Improving the Human Mind". Under it, he imagined a system where people of intellectual labor, working at high-performance computer stations with interactive displays, have access to a vast online information space. With its help, they can cooperate, solving especially important problems. But this system was sorely lacking modern device input. After all, in order to comfortably interact with objects on the screen, you need to be able to quickly select them. NASA became interested in the project and provided a grant to build a computer mouse. The first version of this device is similar to the modern one except in size. In parallel, a team of researchers came up with other devices that allowed you to control the cursor by pressing the foot on the pedal or moving the knee of a special clip under the table. These inventions never caught on, but the joystick, invented at the same time, was later improved and is still used today.

In 1965, D. Engelbart's team published the final report on their research and various methods for selecting objects on the screen. There were even volunteers who participated in testing. It went something like this: the program showed objects in different parts screen and the volunteers tried to click on them as quickly as possible different devices. According to the test results, the first computer mice clearly outperformed all other devices and were included as standard equipment for further research.

What did the first computer mouse look like?

It was made of wood and was the first input device to fit in the user's hand. Knowing the principle of its action, you should no longer be surprised at what the first computer mouse looked like. Under the case there were two metal disk-wheels, a diagram. There was only one button, and the wire went under the wrist of the person holding the device. The prototype was assembled by one of the members of D. Engelbart's team, his assistant William (Bill) English. Initially, he worked in another laboratory, but soon joined the project to create input devices, developed and brought to life the design of a new device.

By tilting and swinging the mouse, you can draw perfectly smooth vertical and horizontal lines.

In 1967, the case became plastic.

Where did the name come from?

No one really remembers who first called this device a mouse. It was tested by 5-6 people, it is possible that one of them voiced the similarity. Moreover, the world's first computer mouse was with a wire-tail at the back.

Further improvements

Of course, the prototypes were far from ideal.

In 1968, at a computer conference in San Francisco, D. Engelbart presented improved first computer mice. They had three buttons, in addition to them, the keyboard was understaffed with a device for the left hand.

The idea was this: the right hand works with the mouse, selecting and activating objects. And the left one conveniently calls necessary commands using a small keyboard with five long keys, like a piano. At the same time, it became clear that the wire at the operator's hand was confused when using the device, and that it needed to be brought to the opposite side. Of course, the prefix for the left hand did not take root, but Douglas Engelbart used it on his computers until the last days.

Continued improvement work

In the later stages of mouse development, other scientists entered the scene. The most interesting thing is that D. Engelbart never received royalties from his invention. Since he patented it as a specialist of the Stanford Institute, it was the Institute that disposed of the rights to the device.

So, in 1972, Bill English replaced the wheels with a trackball, which made it possible to recognize mouse movement in any direction. Since he was then working at Xerox PARC, this innovation became part of the then advanced Xerox Alto system. It was a minicomputer with a graphical interface. Therefore, many mistakenly believe that the first at Xerox.

The next round of development occurred with the mouse in 1983, when Apple entered the game. Enterprising calculated the cost of mass production of the device, which amounted to approximately $ 300. It was too expensive for the average consumer, so the decision was made to simplify the design of the mouse and replace the three buttons with one. The price dropped to $15. And although this decision is still considered controversial, Apple is in no hurry to change its iconic design.

The first computer mice were rectangular or square in shape, the anatomical rounded design appeared only in 1991. It was introduced by Logitech. In addition to an interesting form, the novelty was wireless: communication with a computer was provided using radio waves.

The first optical mouse appeared in 1982. It needed a special pad with a printed grid to work. And although the ball in the trackball quickly became dirty and was an inconvenience that it had to be cleaned regularly, the optical mouse was commercially unprofitable until 1998.

What's next?

As you already know, "tailed" trackballs are practically not used anymore. Technology and ergonomics of computer mice are constantly improving. And even today, when touchscreen devices are becoming more and more popular, their sales do not fall.