CN104317056A - Optical system image quality infrared heating compensating device - Google Patents

Abstract

The invention discloses an optical system image quality infrared heating compensating device and belongs to the field of optical image quality compensating of an optical system. The problems that in the prior art, the structure is complex, compensating accuracy is low, and a Zernike aberration compensating component item number is limited are solved. An optical element is fixed on an optical frame, and n light beam expanding devices are fixed in laser spot outlet holes of the optical frame through flanges respectively. A whole infrared heating compensating system is arranged on an optical platform in a covering mode through an acrylic cover. The infrared heating compensating system comprises a laser device and n groups of heating systems. Light emitted out by the laser device is subjected to light splitting of a light splitter and is emitted into the n groups of heating systems through a full-reflecting mirror respectively. Light transmission devices of the n groups of heating systems are connected with the light beam expanding devices through locating sleeves. Light emitted into the heating systems is subjected to attenuation through a light beam power attenuation device and then is irradiated to the optical element through the light transmission devices and the light beam expanding devices which can adjust out-light direction, and image quality compensating is achieved.

Description

An optical system image quality infrared heating compensation device

technical field

The invention belongs to the field of optical image quality compensation of optical systems, and in particular relates to an infrared heating compensation device for optical system image quality.

Background technique

With the rapid development of the field of optical applications, the requirements for the resolution and productivity of the optical system continue to increase. The increase in the number of lenses and the increase in the exposure dose can effectively improve the resolution and productivity of the optical system, but the adoption of the above methods is inevitable. The introduction of the aberration of the optical system causes the optical system to fail to meet the design specifications, which makes the infrared heating compensation device for the image quality of the optical system very necessary.

The optical system image quality compensation technology in the prior art includes passive compensation technology based on structural optimization, and active compensation technology based on deformable mirror. The heat conduction and heat transfer efficiency in some areas will change the temperature distribution of the lens, thereby changing the wavefront. The passive compensation technology has limited number and ability to compensate Zernike aberration components, and the compensation accuracy is low; active compensation based on deformable mirror The technology is to apply a load force on the specified area of the lens or frame according to the components to be compensated, so that the lens is deformed, and then the wavefront is compensated. This technology is complex in structure, expensive, and the number of components to compensate for Zernike aberration is limited.

Contents of the invention

The object of the present invention is to propose an infrared heating compensation device for optical system image quality, which solves the problems of complex structure, low compensation precision and limited number of compensation components for Zernike aberration existing in the prior art.

In order to achieve the above object, a kind of optical system image quality infrared heating compensation device of the present invention comprises picture frame, flange, light beam expander, optical table, infrared heating compensation system and acrylic cover; Optical element is fixed on the picture frame, picture frame n laser spot light exit holes are evenly distributed on the circumference, and the n light beam expanders are respectively fixed in the laser spot light exit holes through flanges;

An infrared heating compensation system is provided on the optical platform, and the infrared heating compensation system is covered on the optical platform through an acrylic cover as a whole. The infrared heating compensation system includes a laser and n groups of heating systems, and the structures of groups 1 to n-1 are the same. It includes a beam splitter, a beam power attenuation device, a light transmission device that can adjust the direction of the outgoing light, and a positioning sleeve. The nth group includes a full reflection mirror, a beam power attenuation device, a light transmission device that can adjust the direction of the outgoing light, and a positioning sleeve; The emitted light of the laser is respectively incident into n groups of heating systems through the beam splitter and the total reflection mirror;

The light transmission device of the n-group heating system is connected to the light beam expander through a positioning sleeve, and the central light emitted from the exit of the light transmission device is coaxial with the axis of the light beam expander and is incident into the heating system After being attenuated by the beam power attenuation device, the light is irradiated onto the optical element through the light transmission device and the light beam expander that can adjust the direction of the outgoing light, so as to realize image quality compensation.

The frame is circular, the diameter of the laser spot light outlet hole is larger than the light aperture of the light beam expander, the flange is fixed on the flange installation reference surface of the laser spot light outlet hole by bolts, and the light beam expander The included angle θ between the central ray emitted by the beam device and the intersection point of the surface of the irradiated optical element is equal to the Brewster's angle of the material of the optical element in the infrared band where the laser is located.

The value of n is: n≥2.

The optical element is a transmission mirror or a reflection mirror.

The optical elements fixed on the frame specifically refer to adhesive fixing or clamping fixing.

The infrared light source specifically refers to a CW laser with P-polarized light in the infrared band.

The beam power attenuation device specifically refers to a continuously adjustable attenuator or a polarizer; the beam splitter specifically refers to a beam splitting plate or a beam splitting prism.

The light transmission device that can adjust the direction of the outgoing light specifically refers to a solid-core optical fiber kit or a light guide arm; the light beam expander specifically refers to a beam expander or a collimator.

The light beam expander is connected to the flange through clearance fit; the light beam expander is screwed to the positioning sleeve.

The outgoing light spot of the infrared heating compensation system is irradiated on the upper surface, lower surface, inside or outside the clear aperture of the optical element.

The beneficial effects of the present invention are as follows: in an optical system image quality infrared heating compensation device of the present invention, the laser outputs p-polarized light, which is divided into multiple beam paths by a beam splitter and a total reflection mirror, and each beam passes through a continuously adjustable attenuator. Adjust the beam power and quantity, realize the transmission of light in any direction through the solid-core fiber optic kit, and transform the energy distribution of the spot into a uniform distribution. Each light passes through the positioning sleeve to realize the alignment and transmission of the optical fiber kit and the beam expander. The adjustment of the beam expander makes the diameter of the spot change accordingly, and the control of the position of the spot is realized through the adjustment of the flange.

For the optical components of the device, the input function is the spot power, the spot diameter, the number of spots, and the spot position, and the 37 Zernike coefficients representing the surface shape of the optical component are used as the objective function to establish a transfer function. Through the surface shape index that needs to be compensated, Solve the required spot power, spot diameter, spot number, and spot position; adjust the laser and the continuously adjustable attenuator according to the results obtained by the above algorithm, and realize the control of the spot power; The distance, and the magnification of the beam expander, realize the control of the spot diameter; realize the control of the number of light spots through the continuously adjustable attenuator; realize the control of the position of the light spot through the adjustment of the flange direction; realize the infrared heating compensation of the image quality of the optical system based on the above control . The present invention is based on infrared light source heating to realize the temperature adjustment of the optical element and then change the image quality active compensation technology device of the wavefront of the optical element. The structural design of the device is moderately difficult, the number and ability of compensating Zernike aberration components are strong, and the compensation accuracy is high. Suitable for precision optical systems with high image quality requirements.

Description of drawings

Fig. 1 is a schematic diagram of the mirror group structure in an optical system image quality infrared heating compensation device of the present invention;

2 is a schematic diagram of an infrared heating compensation system in an optical system image quality infrared heating compensation device of the present invention;

Fig. 3 is a schematic diagram of an irradiation spot of an optical system image quality infrared heating compensation device of the present invention;

Among them: 1. Optical components, 2. Mirror frame, 201. Laser spot light exit hole, 3. Flange, 4. Beam expander, 5. Optical platform, 6. Acrylic cover, 7. Laser, 8. Heating system, 801, Spectroscope, 802, continuously adjustable attenuator, 803, fiber optic kit, 804, positioning sleeve, 805, total reflection mirror.

Detailed ways

Embodiments of the present invention will be further described below in conjunction with the accompanying drawings.

Referring to accompanying drawings 1, 2 and 3, an optical system image quality infrared heating compensation device of the present invention includes a mirror frame 2, a flange 3, a beam expander 4, an optical platform 5, an infrared heating compensation system and an acrylic cover 6. An optical element 1 is fixed on the frame 2, and two laser spot light exit holes 201 are evenly distributed on the circumference of the picture frame 2, and the two beam expanders 4 are respectively fixed in the laser spot light exit holes 201 through the flange 3;

The optical table 5 is provided with an infrared heating compensation system, and the infrared heating compensation system is covered on the optical table 5 through an acrylic cover 6 as a whole. The infrared heating compensation system includes a laser 7 and two sets of heating systems 8. The first set of structures includes Spectroscope 801, continuously adjustable attenuator 802, fiber optic kit 803 and positioning sleeve 804, the second group includes total reflection mirror 805, continuously adjustable attenuator 802, fiber optic kit 803 and positioning sleeve 804; the laser 7 out The emitted light is split by the beam splitter 801 and the total reflection mirror 805 respectively enters into two sets of heating systems 8;

The optical fiber sets 803 of the two groups of heating systems 8 are connected to the beam expander 4 through the positioning sleeve 804, and the central light emitted from the exit of the optical fiber set 803 is coaxial with the axis of the beam expander 4 and is incident on the heating The light in the system 8 is attenuated by the continuously adjustable attenuator 802 and then irradiated onto the optical element 1 through the optical fiber kit 803 and the beam expander 4 to realize image quality compensation.

The picture frame 2 is circular, the diameter of the laser spot light exit hole 201 is larger than the light aperture of the beam expander 4, and the flange 3 is fixed on the flange installation reference surface of the laser spot light exit hole 201 by bolts, The included angle θ between the central light emitted by the beam expander and the normal to the intersection of the surface of the irradiated optical element 1 is equal to the Brewster's angle of the material of the optical element 1 in the infrared band where the laser 7 is located.

The optical element 1 is a transmission mirror or a reflection mirror.

The optical element 1 is fixed on the spectacle frame 2, which specifically refers to adhesive fixing or clamping fixing.

The beam splitter 801 specifically refers to a beam splitter plate or a beam splitter prism.

The beam expander 4 is connected to the flange 3 through clearance fit; the beam expander 4 is screwed to the positioning sleeve 804 .

The light spot emitted by the infrared heating compensation system is irradiated on the upper surface, lower surface, inside or outside the clear aperture of the optical element 1 .

The optical system image quality infrared heating compensation device of the present invention irradiates the light spots on the surface of the optical element 1 with two controllable heat sources with adjustable power, diameter, quantity and position and uniform energy distribution.

By adjusting the power, diameter, quantity and position of the exit spot, the temperature distribution and wavefront of the optical element 1 can be changed; the wavefront change amount of the optical element 1 is described by a Zernike polynomial, thereby realizing Zernike aberration compensation of the optical system.

The above are specific implementations of the present invention, but in no way limit the present invention. Any modification or equivalent replacement made within the spirit of the present invention is included in the protection scope of the present invention.

Claims (10)

1. An optical system image quality infrared heating compensation device, characterized in that it comprises a mirror frame (2), a flange (3), a light beam expander, an optical platform (5), an infrared heating compensation system and an acrylic cover (6) The optical element (1) is fixed on the picture frame (2), and n laser spot light exit holes (201) are uniformly distributed on the picture frame (2) circumference, and the n light beam expanders are respectively fixed on the In the light exit hole (201) of the laser spot; The optical platform (5) is provided with an infrared heating compensation system, and the infrared heating compensation system is covered on the optical platform (5) through an acrylic cover (6). The infrared heating compensation system includes a laser (7) and n groups of heating System (8), groups 1 to n-1 have the same structure, including a beam splitter (801), a beam power attenuation device, a light transmission device capable of adjusting the direction of outgoing light, and a positioning sleeve (804), and group n includes a total reflection Mirror (805), beam power attenuation device, light transmission device and positioning sleeve (804) that can adjust the direction of the outgoing light; Incident into n groups of heating systems (8); The light transmission device of the n-group heating system (8) is connected to the light beam expander through a positioning sleeve (804), and the central light emitted from the exit of the light transmission device is coaxial with the axis of the light beam expander The light incident into the heating system (8) is attenuated by the beam power attenuation device, and then irradiated on the optical element (1) through the light transmission device and the light beam expander capable of adjusting the direction of the outgoing light, so as to realize image quality compensation. 2. An optical system image quality infrared heating compensation device according to claim 1, characterized in that the mirror frame (2) is circular, and the diameter of the laser spot light exit hole (201) is larger than that of the beam expander Clear aperture, the flange (3) is fixed on the flange installation reference plane of the laser spot light exit hole (201) by bolts, the central light emitted by the light beam expander and the irradiated optical element (1) The included angle θ of the normal direction of the surface intersection is equal to the Brewster's angle of the material of the optical element (1) in the infrared band where the laser (7) is located. 3. An optical system image quality infrared heating compensation device according to claim 1, characterized in that, the value of n is: n≥2. 4. An optical system image quality infrared heating compensation device according to claim 1, characterized in that the optical element (1) is a transmission mirror or a reflection mirror. 5 . The infrared heating compensation device for optical system image quality according to claim 1 , characterized in that, the optical element ( 1 ) is fixed on the mirror frame ( 2 ), specifically refers to adhesive fixing or clamping fixing. 5 . 6. An optical system image quality infrared heating compensation device according to claim 1, characterized in that the infrared light source specifically refers to a P-polarized continuous laser (7) in the infrared band. 7. A kind of optical system image quality infrared heating compensation device according to claim 1, characterized in that, said beam power attenuation device specifically refers to a continuously adjustable attenuator (802) or a polarizer; said beam splitter ( 801) specifically refers to a beam-splitting plate or a beam-splitting prism. 8. An optical system image quality infrared heating compensation device according to claim 1, characterized in that, the light transmission device capable of adjusting the direction of outgoing light specifically refers to a solid-core optical fiber kit (803) or a light guide arm; The light beam expander specifically refers to a beam expander (4) or a collimator. 9. A kind of optical system image quality infrared heating compensator according to claim 1, is characterized in that, described light beam expander and flange (3) are connected through gap fit; Described light beam expander and described The positioning sleeve (804) is threaded. 10. An optical system image quality infrared heating compensation device according to claim 1, characterized in that, the outgoing light spot of the infrared heating compensation system is irradiated on the upper surface, the lower surface and the clear aperture of the optical element (1) or outside the clear aperture.