For the goal is to see without being seen, was tried for decades to come one step closer to using technology that goal. The better this succeeded, the more complex is the technology of night vision devices. The costs of development and the products played a role in more military. In addition to military purposes applications are usually limited in the scientific or civil sector or, as with night target devices, prohibited and associated with great cost. Despite everything, a civilian market for such devices has developed.
Since the end of the “Cold War” get more and more low-light easterly production in the trade. Were they for the time being the military reserved, currently simple night vision devices have become available for civilian users such as security companies, hunters, nature observers or boatmen and also affordable. The spectrum ranges from about Nachtsichtmonokularen Nachtsichtbiokulare or -binokulare to night vision goggles.
The term “low-light” has been attentive to the principle underlying phenomenon of “amplification” of existing “residual light”. Each transmitter and also any electromagnetic radiation from hot object is in a certain wavelength range. While there at night to “detect” relatively little to the human eye, yet a staggering amount of infrared radiation is present. A night vision device works accordingly as a “correction spectacles” by collects the radiation of this wavelength, converts electronically, or amplified and emits it as visible light. For this reason, reference is also made “optoelectronic devices” which are either ‘active’ are, in other words, a light source for illuminating the object use, or “passive” use only the residual light.
A night vision device is, start simply, from a lens that collects the residual light and focuses; an image intensifier tube or -verstärkerröhre that converts that converts light into electrons, and this strengthened again into light and an eyepiece, making the relatively small image of the image intensifier tube is increased.
The picture tubes of the first two generations regarding, still to be noted that due to the high acceleration voltage, a certain amount of X-ray radiation is produced. So care should be taken that similar to the tubes in earlier televisions, were hit by the manufacturer of a night vision device, shielding measures, such as lead additives in Okularglas as the tube of a night vision device is extremely close to the head or eye during use. The radiation exposure is of course also dependent on the duration of use.
In future new generations of night vision devices will be in addition to a data input reflection of the enlargement of the field of view, reducing the depth of night vision goggles and a combination or superposition of amplifiers and thermal imaging equipment is relevant. But the technology of the coating has not yet reached the end of its possibilities.
Currently be done to make also for private use, even smaller, better and more cost-effective devices with layers of light-sensitive nanoparticles experiments. However, similar systems are not entirely able to replace conventional vacuum tubes. So it can be assumed that this effect prototypes are under wraps at our suppliers or military and are tested accordingly.