| Holographic sights installed on small arms are used for close quarter combats. They not only have the advantages of straight and convenient aiming and high accuracy, like normal laser designator sights, but also have the merits of effective concealment, fast aiming and low influence of weather and environment. It significantly improves the capability of small arms used in close quarters battles in all weathers. Holographic sights have already been used in special military units in some highly developed countries. However for secrecy, no reports about the key fabrication techniques can be found. In China, so far, there is not any research report and sample about holographic sight.The design and fabrication technique of holographic sight is studied in the project, with the emphases on the fabrication of the key component of the sight ? holographic optical element (HOE). HOE has the advantages of requiring simple fabrication equipments, low cost, light weight, and being able to produce unique optical effect, so it has important application value in ordnance. In the HOE fabricated in the experiment, an aiming dot and a reticle pattern were recorded. When illuminated by the light from a laser diode (LD), a bright and clear reticle image close to the aiming eye and a virtual point image far away from the shooter.are reconstructed. The shooter can take aim quickly and snugly. In order to mass-produce the HOE so as to reduce the cost, photoresist is used as the recording material, and blue laser is used as the light source. Considering the handiness and cost reduction of holographic sight, red LD is chosen as the illuminating source. Since the wavelengths of recording and illuminating lights are different and LD has relatively wide spectral line-width, the quality of reconstructed image of HOE is affected. For fabricating desired HOE, theoretical analysis on object/image relation, diminishing the third-order aberrations and eliminating image blur were carried out. The results provide effective guidance for optimizing the optical system of HOE fabrication.In HOE fabrication, the reticle and aiming dot are recorded respectively to the same... |
