CN201974104U - Foldable optical system of holographic sight - Google Patents

Abstract

A foldable optical system of a holographic sight relates to a holographic sight. The foldable optical system of the holographic sight has the following advantages: capability of causing light beam to perform folded operation horizontally for reducing transverse dimension of the system, adoption of two reflectors for an optical component which guides the light beam instead of the lens, reduced cost and high convenience in optical path adjustment. The foldable optical system of the holographic sight is provided with a laser diode, a first reflector, a second reflector, a holographic lens and a transmission type hologram. The laser diode is used for transmitting the visible light wave and providing a light source for the system. The first reflector is obliquely placed in front of the laser diode, and the second reflector is obliquely placed above the first reflector and the laser diode. The holographic lens is vertically provided in front of the second reflector. The transmission type hologram is provided at a rear and upper position of the holographic lens. A hologram cross line virtual image is generated in a horizontal direction in front of the transmission type hologram for aiming under the irradiation of the parallel laser beam.

Description

Folded Holographic Sight Optical System

technical field

The utility model relates to a holographic sight, in particular to an optical system of a folding holographic sight.

Background technique

The holographic sight is the latest sighting device used on firearms in the world at present, and can be used for fighting or hunting. It uses a holographic crosshair virtual image created by a hologram for aiming. During the aiming process, regardless of the weather, environment, and light, the crosshair image is clearly visible. It has the characteristics of fast aiming, high precision, and is not affected by environmental conditions. It is especially suitable for use in close-range gun battles or against fast-moving targets. Therefore, in recent years, holographic sights have been highly valued by various countries.

The key part of the structure of the holographic sight is the optical system, and there have been many inventions related to the optical system of the holographic sight so far. Although the optical systems disclosed in these inventions can all produce holographic images for aiming, they all have relatively large practical problems. A practical holographic gun sight optical system should meet the following conditions: (1) compact structure so that the entire holographic gun sight device will not be too long or too high; (2) the image of the holographic crosshair is clear and the image position during use Do not drift, so as to achieve precise aiming.

Although the optical system disclosed in Chinese patent CN200420074252.0 is very simple, its fatal disadvantage is that the angle of the holographic image will change due to the influence of temperature during use, so that the aiming accuracy cannot be guaranteed. The optical system disclosed in US Pat. No. 6,490,060 uses a vertically folded optical path structure to make the system compact; and uses a grating to complement the diffraction of the hologram, thereby limiting the drift of the hologram. However, since the grating has an inclination angle relative to the hologram, the drift of the holographic image caused by the wavelength change cannot be completely eliminated, so the aiming accuracy will still be affected to a certain extent. The holographic gun sight optical system disclosed in Chinese patent 200810071050.3 uses a holographic lens to replace the grating and concave mirror in US patent US6490060, so the system is simpler and lower in cost. However, since the holographic lens and the hologram have an oblique angle, the problem of the holographic image drifting with temperature cannot be completely eliminated. The optical system disclosed in Chinese patent 200910250486.3 adopts a method of matching a holographic optical element with a hologram, which can completely eliminate the problem of holographic image drifting with temperature. However, the optical system in Chinese patent 200910250486.3 has two relatively large problems: (1) the system uses a biconcave lens to expand the laser beam emitted by the laser diode (LD), and the LD, biconcave lens and holographic lens are installed in the system placed on a horizontal line. Although the biconcave lens can further expand the diffusion angle of the laser light emitted by the LD, but to expand the laser beam to a sufficient area, the distance between the LD, the biconcave lens and the holographic lens must be extended. In addition, since the holographic lens is transmissive, the hologram must be placed behind it, causing all components in the system to be arranged laterally, so the optical system is still relatively long in the horizontal direction, and its practicability is poor. (2) When adjusting the optical path, the centerline of the laser beam emitted by the LD must pass strictly through the center point of the concave lens, so that the beam diffused by the concave lens can expand symmetrically relative to the optical axis, so as to obtain a non-deformed crosshair image. Since the alignment of the beam center line and the concave lens center involves adjustments in multiple directions up, down, left, and right, this makes the optical path adjustment of the optical system more troublesome. Therefore, the system disclosed in Chinese patent 200910250486.3 is less feasible in actual production.

Contents of the invention

The purpose of this utility model is to provide a light beam that can be folded horizontally to reduce the lateral size of the system. The optical element that guides the light beam uses two mirrors instead of lenses, which not only reduces the cost, but also facilitates the adjustment of the optical path. Folded holographic sight optics.

The utility model is provided with a laser diode (LD), a first reflector, a second reflector, a holographic lens and a transmission hologram;

Laser diodes are used to emit visible light waves to provide light sources for the system; the first reflector is placed obliquely in front of the laser diode, and the second reflector is placed obliquely above the first reflector and laser diode; the holographic lens is placed vertically in front of the second reflector , convert the beam expansion light reflected from the second mirror into parallel light and run upwards to the hologram; the transmission hologram is placed behind and above the holographic lens, and is horizontally in front of the transmission hologram under the irradiation of parallel laser beams Direction creates a hologram crosshair virtual image for aiming.

The laser beam emitted by the laser diode is divergent light and runs along the horizontal direction; the distance between the laser diode and the holographic lens is preferably equal to the focal length of the holographic lens.

The first reflector and the second reflector are used to form the optical path of the system into a folded structure. The first reflector and the laser diode are placed on the same horizontal line, facing the laser diode and placed obliquely so that the reflected light runs obliquely upward. The second reflector The mirror is placed obliquely above the first reflector and the laser diode, and reflects the laser beam reflected from the first reflector to the horizontal direction.

The holographic lens converts the expanded beam reflected by the second reflector into parallel light to be used as the illumination light of the hologram, and the holographic lens can also filter out unnecessary wavelengths in the laser light by virtue of the diffraction function.

The holographic lens and the transmission hologram preferably have the same spatial frequency.

The center line of the reflected light of the second reflecting mirror is in the horizontal direction and is vertically incident on the holographic lens.

The transmission hologram is preferably placed vertically above and behind the holographic lens, and the transmission hologram and the holographic lens achieve complete diffraction matching.

The utility model has the characteristics that:

1) The laser beam is guided by two reflectors to form a zigzag optical path structure with upper and lower layers, which greatly shortens the lateral size of the system; at the same time, because the two reflectors are placed obliquely, the upper and lower layers of optical components can be very close close, so there is no appreciable increase in vertical dimension.

2) Reflectors are used instead of lenses for beam guidance, which not only reduces costs, but also does not require center alignment between the laser diode and the two reflectors, which greatly simplifies the difficulty of optical path adjustment.

3) The laser diode and the first reflector are arranged at the bottom of the optical path, and they can be easily moved to meet the focal length requirement of the holographic lens. At the same time, as long as the inclination angle of the two mirrors is adjusted, the traveling direction of the light beam can be controlled. Therefore, the optical system of the present invention has the advantages of compact structure, low cost and convenient adjustment.

Compared with Chinese patents CN200420074252.0, CN200810071050.3, and US patent US6490060, the optical system of the present invention can provide a clear holographic cross-filament image that does not drift with environmental changes, thus ensuring precise aiming. Compared with Chinese patent CN200910250486.3, the optical system of the present invention is simple to adjust, has a shorter lateral dimension, and lower cost, and has higher practicability and feasibility.

Description of drawings

Fig. 1 is a schematic diagram of the structure and composition of an embodiment of the utility model.

Detailed ways

The following embodiments will further illustrate the utility model in conjunction with the accompanying drawings.

In Fig. 1, mark 1 is a laser diode, 2 is a first reflector, 3 is a second reflector, 4 is a holographic lens, 5 is a transmission hologram, 6 is a human eye, and 7 is a holographic crosshair virtual image. The laser diode 1 and the first mirror 2 are placed at the bottom of the system, the second mirror 3 and the holographic lens 4 are placed at the second layer of the system, and the hologram 5 is placed at the top of the system. The laser diode 1 is placed horizontally, and the laser light emitted by it runs along the horizontal direction and reaches the first reflector 2 placed obliquely. The reflected light from the first reflecting mirror 2 travels obliquely upward to reach the second reflecting mirror 3 . The reflected light of the second reflecting mirror 3 is vertically incident on the hologram lens 4 . Both the holographic lens and the hologram 5 are placed vertically. The light beam emitted from the holographic lens changes from divergent light to parallel light, and runs upward at a certain angle to reach the hologram. The human eye 6 can see through the hologram from the rear of the hologram that there is a holographic crosshair virtual image 7 in the horizontal direction in the distance.

The fabrication methods of holographic lenses and holograms are described in detail in holographic textbooks and some optical textbooks.

Claims (6)

1. collapsible holographic aiming device optical system is characterized in that being provided with laser diode, the 1st speculum, the 2nd speculum, hololens and transmissive hologram;

Laser diode is used for the visible emitting ripple, for system provides light source; The 1st mirror tilt is positioned over laser diode the place ahead, and the 2nd mirror tilt is positioned over the 1st speculum and laser diode top; Hololens vertically is positioned over the 2nd speculum the place ahead; Transmissive hologram places the back upper place of hololens, produces the virtual image of a hologram cross hair in transmissive hologram the place ahead horizontal direction under the collimated laser beam irradiation, is used for aiming.

2. collapsible holographic aiming device optical system as claimed in claim 1 is characterized in that described laser diode equals the focal length of this hololens to the distance of hololens.

3. collapsible holographic aiming device optical system as claimed in claim 1 is characterized in that described the 1st speculum and laser diode place on the same horizontal line, towards the laser diode and the placement of tilting.

4. collapsible holographic aiming device optical system as claimed in claim 1 is characterized in that described hololens and transmissive hologram have identical spatial frequency.

5. collapsible holographic aiming device optical system as claimed in claim 1, the catoptrical center line that it is characterized in that described the 2nd speculum is normally incident in hololens in the horizontal direction.

6. collapsible holographic aiming device optical system as claimed in claim 1 is characterized in that described transmissive hologram vertically is positioned over the back upper place of hololens.