What is the reason for mouse sensitivity reduction

Sensitivity variation is a common fault of the optical mouse, the specific performance of mobile mouse, the cursor should be slow, do not listen to command. The failure of the original and solution is:

1 light-emitting Tube or photosensitive element aging: The core IC of the optical mouse has a constant current circuit, the working current of the luminous tube is constant in about 50mA, the high grade mouse generally uses the intermittent sampling technology, the current that sends out is intermittent conduction (sampling frequency is about 5KHz), The power of the luminous tube can be improved under the same power consumption, so the detection sensitivity is high. Some manufacturers in order to improve the sensitivity of the optical mouse, artificially increased the light-emitting diode operating current, increasing the launch function. This can lead to the early aging of light-emitting diodes. At the receiving end, if the quality of the photosensitive transistor is not high, the working time is long, will also natural aging, resulting in sensitivity to become worse. At this point, only the replacement model of the same light-emitting tube or photosensitive tube.

2 The photoelectric receiving system is offset, the focal length is not aligned. Optical Mouse is the use of internal two pairs of photoelectric detectors perpendicular to each other, with the photoelectric board to work. The light emitted from the light-emitting diode shines on the photoelectric board, after which the reflected light is reflected again through the reflector, adjusts the transmission path, receives the photosensitive tube, forms the pulse signal, and the number and phase of the pulse signal determines the speed and direction of the mouse movement. The transmitter and lens system components of the optical mouse are assembled in one, fixed on the mouse shell, and the photosensitive transistor is fixed on the circuit board, the location of the two must be quite accurate, the manufacturers are in the calibration position, with hot melt glue to the light-emitting tube fixed on the lens assembly, if the use of the process, the mouse was touched or vibration too large, It is possible to get the hot melt adhesive off and the light-emitting diode shift. If the light-emitting diode deviates from the calibration position, the light reflected from the photoelectric board may not reach the photosensitive tube. At this point, we have to patiently adjust the position of the light-emitting tube, so that it restores in situ, until the horizontal and vertical direction of movement, the pointer is the most sensitive, and then with a small amount of 502 glue fixed the position of the light-emitting tube, close the cover plate can be.

3) external light influence. In order to prevent the influence of external light, the bare part of the lens component is concealed by the opaque black paper, so that the light is transmitted in the black box, if the dark paper falls off, causing the external light to illuminate the photosensitive tube, it will make the photosensitive tube saturated, the data processing circuit can not get the correct signal, resulting in lower sensitivity.