It is difficult for a modern user of a personal computer to imagine interacting with him without a computer mouse. The device, the purpose of which is to perform the most elementary tasks, has a small size, rather low price and seemingly insignificance. But at the same time, most of the actions performed by users are connected with it.
As an input device, a computer mouse was born seven years before the first PC and three years before the creation of the first microprocessor. The product was called MOUSE (allegedly collecting the designation Manually Operated User Signal Encoder in the abbreviation), and it was developed by the American space agency for the fast and accurate transfer of coordinates. However, the device obtained by the engineers, which in shape and size did not resemble a mouse at all, but the most natural iron, did not meet the required tasks. Therefore, the project was closed, and in the usual form of users, the mouse entered the market in the late seventies, and it was by no means a PC, but the brainchild of Apple, the first computer with a full graphical interface. It is from this moment that the evolution of the "rodents" known to the masses begins.
Mouse purpose
A computer mouse is an information input device, the principle of which is based on the transfer of coordinates to a computer, their processing by the processor, subsequent display of the corresponding cursor position on the screen, as well as interaction with interface elements through control buttons. Opening files, scrolling windows and pages of sites, calling the context menu and selecting commands from it, moving and copying - most of these and other operations (apart from typing, of course) are performed by an ordinary computer user using the mouse.
Varieties
There are two main types of "electronic rodents": mechanical and optical. Among those, and others there are varieties due to technological differences.
Mechanical devices
Due to the imperfection of technology, computer mice of this group are no longer manufactured and practically never used, being completely superseded by their more modern and practical counterparts.
The initial design of the mouse involved taking coordinates through the rotation of two wheels perpendicular to the wheels (the very first manipulator was designed this way), but the general public remembered the ball drive, since it was these mice that were mainly used until the late nineties.
The basis of the internal device of a mechanical-type computer mouse is a rubber ball covered in rubber that extends beyond the lower limits of the case. Metal gives the manipulator the necessary weight, and rubber - adhesion to the surface. Inside the body, the ball is pressed against two rollers, the movements of which are recorded by sensors, and then converted into electrical impulses. In the first models of mechanical computer mice, the sensor device assumed contact connection with the rollers, in later versions they were replaced by photosensitive optical ones, and the rollers acquired plates with special perforations designed to transmit or delay the light flux from the source.
The main drawback of ball-driven mice is the constant need for cleaning and maintenance. Dust, small debris, particles of hair and skin - all this ball was pulled into the mouse body with an enviable constancy. As a result, the rollers were covered with layers of pollution (up to two to three millimeters thick), and the ball itself evenly distributed these deposits over its entire surface, thereby reducing the sensitivity and accuracy of the mouse. In addition, it was rather difficult to use the mouse without a special mouse pad, which improved mouse grip and reduced (although not very much) the likelihood of contamination.
Optical devices
This type of computer mouse was developed back in 1980, but the product became widespread in the late nineties, when Hewlet Packard devices under the Microsoft brand name appeared on the market.
The first generation manipulators quite seriously differed from optical computer mice familiar to the modern user. Sensors in the form of an optical pair were installed inside the device: emitting and absorbing reflected light from the surface, respectively. And on this very surface special technical drawings had to be present, which made the use of a mouse without an appropriate rug pointless. And since the pattern for each of the sensors could be individual, then there was no question of any compatibility. In addition, many users were frightened by the rather high price of such devices.
The next generation of optical “rodents” was already deprived of the shortcomings of previous models: now a special video camera monitors mouse movements on the surface, continuously photographing it and comparing each image with the previous one. Bright light (in simple models) at the bottom of the device is a backlight that increases the efficiency of the camera. Most often, red LEDs are used, in more expensive models, the backlight may be different. There is no binding to special rugs: the mouse can be used on most surfaces (except for glasses, mirrors and similar surfaces).
In the presented image, you can disassemble the Defender computer mouse device: how the LED forms a beam, how it reflects from the surface, and then gets on the light trap.
Laser devices
One of the subspecies of optical manipulators. With completely identical operating principles, laser mice differ from the classic "optics" only by the installed laser infrared diode. The light emitted by the diode is focused using a lens into a micro-point, then it is reflected and captured by an ultra-precise and ultra-sensitive sensor. Due to more accurate focusing, the use of this type of backlight makes the device much less dependent on the type of surface used. This is expressed in the possibility of using laser mice on glass and mirror coatings. In addition, manufacturers of such devices promise increased sensor accuracy, which can significantly help representatives of the gaming industry (the statement is quite controversial, and more like a marketing ploy).
There is no bright illumination, since light in the infrared range is not perceived by the human eye. Accordingly, the problem of constant operation of the backlight LED even when the computer is off (as noted by many users of optical mice) for laser mice is uncharacteristic.
Induction devices
A rare variety of computer mice. The device of most of these manipulators is no different from ordinary optical mice. The difference, most often, lies in obtaining power: usually these mice are included in the set of graphic tablets and receive power from these tablets on the principle of electromagnetic induction - through the interaction of the transmitting and receiving induction coils located in the tablet and in the mouse body, respectively.
The practical use of such a device for the average user will tend to zero, but for graphic designers who often cherish every centimeter of space on the table, such a solution will appeal to you.
Gyroscopic devices
The presence of a gyroscope in many consumer electronics devices has long been the norm. And the IT industry is no exception, where not only smartphones and tablets are equipped with gyroscopes, but also virtual reality devices, as well as computer mice.
A feature of such a rodent is the ability to work not only in the horizontal plane (in this case, it works like an ordinary optical mouse), but also in space. The sensor readings are recorded in the same way by the computer, which allows you to move the cursor on the screen without installing the manipulator on a hard surface.
Trackballs
A stand-alone device equipped with a ball that performs functions similar to a classic ball mouse, but is located not from below, but from above or from the side. The cursor moves around the screen due to the movement of fingers or palms around the ball, the indicators of the rollers are taken by highly sensitive optical sensors, which, according to the developers, assures that the negative effects of pollution are minimized.
Such controllers did not win special love for the majority of users (the price turned out to be an important factor), narrowing the main scope to music, medical and military. The most famous manufacturer of such devices is Logitech. Computer mice and other manipulators of this company are very popular, but in the field of non-standard controllers it is far from last.
Wired and wireless devices
There is a distinction and type of power source. The very first mass devices received their five Volts exclusively from the computer's power supply (regardless of the type of connector - PS / 2 or USB), and, accordingly, were wired. Wireless manipulators, on the other hand, operate from their own power sources (batteries or accumulators), and they, in the process of introducing wireless technologies into the IT industry, underwent certain changes.
Infrared communication
The very first attempt to establish a wireless connection between a computer and a pointing device. A special transmitting unit was connected to the computer, the signal from which came to the receiving device on the mouse itself. At this point, the main drawback of optical communication was hidden: the connection required direct visibility between the receiver and the transmitter, which was often complicated due to the appearance of certain obstacles, as well as due to the banal movement of the mouse by an unacceptable angle. To date, the release of such devices has been discontinued.
Radio Channel and Bluetooth
In fact, both are designations of identical data transmission methods. The difference lies in the use of communication standards: Bluetooth is a standardized protocol, and any mouse that supports the standard synchronizes with the transmitter without problems, while ordinary wireless mice require a strictly defined adapter connected to a USB port. If the adapter is broken or lost (and considering its tiny size, the probability of this is not so small), then the mouse turns into a useless piece of plastic, since it will not work with another adapter (including Bluetooth).