Sensors, as the name suggests, are particularly sensitive to certain things. A variety of types of sensors can detect almost any information, in particular, the photoelectric sensor can detect visible light, infrared radiation, microwave, radio signals, etc.. The signal output from the sensor is usually sent to other electronic equipment for processing. The technology of sensor and signal processing device is very important, and it is also very complex. With the rapid development of optoelectronic technology, all kinds of photoelectric sensors in a variety of military equipment and weapons systems have been increasingly widely used. Photoelectric sensors have become an important part of a wide range of electronic equipment widely used in command, control, communications, and intelligence, that is to say, both the laser range finder, or laser radar, or a variety of laser guidance system, are inseparable from a certain type of sensor.

Photoelectric sensor is like the "eye" of the fire control system of weapon, they leave, radar and laser range finder won not reflected by the target back laser, to the distance of the target and other motion parameters were measured, and laser guided missiles and bombs can keep tracking and accurately hit the target. Generally speaking, a gold is to track the target missile "blind" to than to an ordinary soldier blindness has higher benefit. Therefore, sensor like the human eye as the main target of the low energy laser weapon, even is the main targets of low energy laser weapons. Not to mention, eye blinding laser weapons will by humanitarian condemnation and banned, and attack the sensor of laser weapons are not any censure. The damage of the laser to the sensor is also based on the same mechanism. Even though the radiation incident to the sensor window is rather weak, the high energy density of the detector can be obtained due to the convergence of the optical elements.

A typical photoelectric sensor usually contains a lot of optical elements, beam of light to enter the sensor after repeated convergence, detector surface actual incident energy density can be as high as exposure to 100 million times the energy density of sensor surface the cornea in the retina of energy density gain is of the same order of magnitude. Sensor is designed such that the purpose is to improve the sensitivity and to have the ability of an extremely weak light detection; unfortunately, the characteristics of the become easily affected by the goal of laser weapon damage. Because the photoelectric sensor for infrared radiation, or visible light, or the two are particularly sensitive, and thus more likely to become the target of laser attacks. In addition, the electronic system and the sensor itself is also very easy to be generated by laser thermal noise and electromagnetic noise interference and can not work properly. On the battlefield laser weapons to attack the photoelectric sensor mainly in the following several: with proper energy of the laser beam sensors will be "blind" the cannot detect or continue to have detected the target tracking. Or, if the sensor is guided weapon to the target, it will lose its target of blindness. When the sensor of the warhead of the missile and bomb is disturbed or decoy, it will either make it stay away from the target prematurely and will not harm its intended target, or it will not explode at all. The electronic device or sensor failure of key components, resulting in a weapons system failure and miss. Due to the sensor itself or optical system thermal damage or physical damage, can also lead to a weapons system failure and miss. Most of the sensor works within a limited range of wavelength, different sensors have different working wavelengths, in general, sensor, the longer wavelength, wavelength range is wide, the higher sensitivity of the sensor and more easily by laser beam attack. One of the most vulnerable sensors is the working wavelength range of 8-12 microns to detect the thermal radiation of the sensor. The reason why this band radiation is called thermal radiation, is because the ordinary warm objects, such as soldiers, are working aircraft and tanks of the engine will spontaneously generate this band of radiation. Therefore, the sensor on the military night vision system is particularly sensitive to the band, so as to effectively detect a class of targets as described above at night.

Typically, the other thermal infrared photoelectric sensor homing missile using wavelength slightly shorter than the above. This missile is mainly used to attack aircraft. Appropriate wavelengths of infrared laser can be used as a decoy to induce the missile to fly along the wrong path, or the sensor completely destroyed, so that the missile completely changed into a blind". One of the important goals of laser weapon is "fuze". The fuse is pre programmed to explode when the weapon is sufficiently close to the target and destroy it. Most modern information dependent on a photoelectric sensor, for example, in a lot of anti aircraft missile photoelectric sensor including a small, low power semiconductor laser emits a short pulse laser, laser returned by the target is receiving detector. If the pulse is emitted in a very short period of time to receive the reflected light, it means that the target is very close to. When the target is close enough, the warhead is detonated. The missile tracking the pilot of the plane that can be taken to counter measures is, when the missile is far enough away. Its explosion will not cause any harm to use laser decoy target fuze device will detonate the missile; either with sufficiently high energy laser beam will fuze set destroyed. So the missile will not be detonated. Can also be used on the battlefield