A large-field-of-view transmission-type high-energy laser emission system

Abstract

To address the shortcomings of existing transmissive systems, which have a small field of view, hindering target detection and search, and increasing the system aperture, this invention proposes a large-field-of-view transmissive high-energy laser emission system. The system comprises a common-aperture telescope system, an oscillating mirror, a beam combiner, and a receiving lens. Laser light, after being transmitted through the beam combiner and reflected by the oscillating mirror, is emitted through the common-aperture telescope system. Visible light, after passing through the common-aperture telescope system, is reflected by the oscillating mirror and the beam combiner before being received by the receiving lens. This invention is suitable for miniaturizing high-energy laser emission systems.

Description

Technical Field

[0001] The present invention relates to the field of high-energy laser emission systems, and in particular to a large-field-of-view transmission-type high-energy laser emission system. Background Art

[0002] The continuous increase in the output power of semiconductor lasers has driven a wave of research and development of high-energy laser launch equipment. This equipment features long working distance, high output energy, and a common optical path for tracking and aiming. This allows the tracking and aiming position to be aligned with the laser's far-field convergence position. The system achieves continuous focusing of the laser on the target's designated location by stably tracking the target. Existing high-power laser launch systems are divided into two types: reflective and refractive. Reflective systems are affected by off-axis aberrations, which limit the scanning field of view. Existing transmissive systems increase the system's aperture because laser scanning increases the system's optical aperture. High-energy laser systems cannot block the beam like traditional optical systems. Due to the limited processing aperture of the transmissive lens, the scanning field of view cannot be expanded. Existing systems all have a small field of view, with both the instantaneous field of view and the scanning field of view within 10', which is not conducive to target detection and search. Furthermore, the system's turntable precision requirements are too high, increasing the overall system cost. Furthermore, during the laser scanning process, the high-energy laser beam moves at the system's launch port, increasing the system aperture and hindering the miniaturization and lightweighting of the equipment. Summary of the Invention

[0003] One purpose of the present invention is to solve the defect of the prior art transmission system that the field of view is small, which is not conducive to the detection and search of the target and increases the system aperture.

[0004] The present invention provides a large-field-of-view transmission-type high-energy laser emission system, comprising: a common-aperture telescope system, a swing mirror, a beam combiner, and a receiving lens; the laser is emitted through the common-aperture telescope system after being transmitted by the beam combiner and reflected by the swing mirror; the visible light is received by the receiving lens after passing through the common-aperture telescope system and being reflected by the swing mirror and the beam combiner.

[0005] Preferably, the exit pupil is located at the first optical surface of the common aperture telescopic system.

[0006] Preferably, the entrance pupil is located at the swing mirror.

[0007] Preferably, the common-aperture telescope system is a secondary imaging design, and the focus is actually concentrated in the quartz structure.

[0008] Preferably, the common-aperture telescopic system includes a negative lens group and a positive lens group along the laser emission direction.

[0009] Preferably, the oscillating mirror realizes the scanning function of emitting laser light and detecting the field of view through two-dimensional oscillation.

[0010] Preferably, the beam combiner has a coating, which enables the laser to be transmitted through the beam combiner and enables the visible light to be reflected on the surface of the beam combiner.

[0011] Preferably, the wavelength band of the laser is 1080±5 nm.

[0012] Preferably, the wavelength range of visible light is 480 nm to 650 nm.

[0013] Preferably, the system further comprises a folding mirror for reflecting the laser beam to achieve the effect of folding the light path.

[0014] The beneficial effects of the present invention are:

[0015] 1. Increase the system scanning field of view, reduce the difficulty of system detection and search, lower the system's accuracy requirements for the turntable, reduce the system cost, and the laser spot does not change at the system exit during the system scanning process.

[0016] 2. The system adopts a common optical path design for laser emission and reception, which can simultaneously realize the detection of long-distance targets and high-energy laser emission functions. The system's detection field of view can reach 1.5°, and the scanning field of view can reach 1.5°, which is much larger than the field of view within 10' in existing technologies.

[0017] 3. The system achieves pupil coupling through secondary imaging. The entrance pupil is designed at the position of the swing mirror, and the exit pupil is coupled to the position of the first lens in the system group. This ensures that the laser spot remains at the system exit position during the swing mirror scanning process, effectively increasing the system aperture utilization. In one embodiment, the system aperture is 90mm and the light exit aperture is 75mm, achieving an aperture utilization rate of 83%. This reduces the system aperture and achieves overall miniaturization and lightweighting of the equipment.

[0018] Further features and advantages of the present invention will become apparent from the following detailed description of exemplary embodiments of the present invention with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

[0020] Figure 1 Schematic diagram of the structure of the large-field-of-view transmission-type high-energy laser emission system of the present invention;

[0021] Figure 2 A structural diagram of an embodiment of the present invention;

[0022] Figure 3 is a visible light band aberration curve of an embodiment of the present invention;

[0023] Figure 4FIG. 4 is an aberration curve of a laser wavelength band according to an embodiment of the present invention. DETAILED DESCRIPTION

[0024] Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that unless otherwise specifically stated, the relative arrangement of components and steps, numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present invention.

[0025] The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses.

[0026] Technologies, methods, and equipment known to ordinary technicians in the relevant art may not be discussed in detail, but where appropriate, the technologies, methods, and equipment should be considered part of the specification.

[0027] In all examples shown and discussed herein, any specific values should be interpreted as merely exemplary and not limiting. Therefore, other examples of the exemplary embodiments may have different values.

[0028] It should be noted that like reference numerals and letters refer to like items in the following figures, and therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0029] The present invention provides a large field of view transmission type high energy laser emission system, such as Figure 1 As shown, including:

[0030] A common-aperture telescope system 10, an oscillating mirror 20, a beam combiner 30, and a receiving lens 40; the laser is transmitted through the beam combiner 30 and reflected by the oscillating mirror 20 before being emitted through the common-aperture telescope system 10; the visible light passes through the common-aperture telescope system 10 and is reflected by the oscillating mirror 20 and the beam combiner 30 before being received by the receiving lens 40.

[0031] The system exit pupil is located at the first optical surface of the common-aperture telescope system 10, and the entrance pupil is located at the swing mirror 20, and the common-aperture telescope system 10 is designed for secondary imaging. The first optical surface refers to the optical element closest to the outside world in the system lens group. The swing mirror 20 realizes the scanning function of the emitted laser and the detection field of view through two-dimensional swinging. This setting can ensure that the laser spot does not change position on this surface during the scanning process of the swing mirror 20, thereby reducing the physical aperture of the system. The real focus of the common-aperture telescope system 10 converges in the quartz structure 15. This setting can ensure that the real focus position of the high-energy laser will not experience breakdown and ionization.

[0032] The common aperture telescope system includes a negative lens group and a positive lens group along the laser emission direction. Figure 2In the illustrated embodiment, the positive lens group consists of 4 lenses, the telephoto negative lens group consists of 7 lenses, the focal length ratio of the front and rear groups is 3:1, and the telescope group beam expansion ratio is 3 times.

[0033] The beam combiner 30 has a coating that allows laser light to pass through the beam combiner 30 and visible light to be reflected from its surface. In one embodiment, the common-aperture telescope system 10 is a system that transmits a common optical path for laser light in the 1080±5nm band and visible light in the 480nm-650nm band. The beam combiner 30 achieves dual-band coupling through the coating, wherein the 1080±5nm band is transmitted through the beam combiner, and visible light in the 480nm-650nm band is reflected from its front surface.

[0034] The system may further include a folding mirror 50, which reflects the laser beam to fold the light path and reduce the volume of the system.

[0035] The receiving lens 40 realizes visible light imaging and provides image information for system detection and tracking.

[0036] <Example>

[0037] Figure 2 An embodiment of a large-field-of-view transmissive high-energy laser emission system is shown. Figure 2 The CCP-caliber telescope system is a secondary imaging design, with the real focus concentrated in a high-purity quartz rod to ensure that there will be no breakdown or ionization at the real focus position of the high-energy laser. The positive lens group consists of 4 lenses, and the negative lens group consists of 7 lenses. The focal length ratio of the front and rear groups is 3:1, and the beam expansion ratio of the telescope group is 3 times. The system entrance pupil is located at the swing mirror position, and the exit pupil is located on the first surface of the system, so that during the swing mirror scanning process, the laser spot does not change position on this surface, reducing the physical aperture of the system; the receiving mirror group consists of 11 transmission lenses, and the system's precise tracking instantaneous field of view is 1.5°, and the scanning field of view is ±0.75°. This field of view is more than 10 times larger than the traditional high-energy laser emission field of view, effectively improving the system's detection capability and reducing the system's accuracy requirements for the turntable.

[0038] Figure 3 and Figure 4 A visible light aberration curve diagram of an embodiment is shown. It can be seen from the diagram that the transfer function of the visible light detection channel is higher than 0.3 at 45 line pairs, and the transfer function of the laser channel is close to the diffraction limit.

[0039] Although some specific embodiments of the present invention have been described in detail by way of examples, it should be understood by those skilled in the art that the above examples are for illustration only and are not intended to limit the scope of the present invention. It should be understood by those skilled in the art that modifications may be made to the above embodiments without departing from the scope and spirit of the present invention. The scope of the present invention is defined by the appended claims.

Claims

1. A large field of view transmission type high energy laser emission system, characterized in that: include: A common aperture telescope system (10), a swing mirror (20), a beam combining mirror (30) and a receiving lens (40); after the laser passes through the transmission effect of the beam combining mirror (30) and the reflection effect of the swing mirror (20), it is emitted through the common aperture telescope system (10); after the visible light passes through the common aperture telescope system (10), it is received by the receiving lens (40) through the reflection effect of the swing mirror (20) and the beam combining mirror (30); the exit pupil position is located at the optical element closest to the outside world in the common aperture telescope system (10), and the entrance pupil position is located at the swing mirror (20); the common aperture telescope system (10) is a secondary imaging design, and the actual focus is concentrated in the quartz structure (15); the swing mirror (20) realizes the scanning function of emitting laser light and detecting the field of view through two-dimensional swinging.

2. The large-field-of-view transmission-type high-energy laser emission system according to claim 1, characterized in that: The common aperture telescopic system (10) comprises a negative lens group and a positive lens group along the laser emission direction.

3. The large-field-of-view transmission-type high-energy laser emission system according to claim 1, characterized in that: The beam combining mirror (30) has a coating, which enables laser light to be transmitted through the beam combining mirror (30) and enables visible light to be reflected on the surface of the beam combining mirror (30).

4. The large-field-of-view transmission-type high-energy laser emission system according to claim 1, characterized in that: The wavelength of the laser is 1080±5 nm.

5. The large-field-of-view transmission-type high-energy laser emission system according to claim 1, characterized in that: The wavelength range of the visible light is 480nm to 650nm.

6. The large-field-of-view transmission-type high-energy laser emission system according to claim 1, characterized in that: It also includes a folding mirror (50) for reflecting the laser beam to achieve the effect of folding the light path.

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