Coupling telescope adaptive DMD chip inclined image plane accurate imaging transfer optical lens

Abstract

The invention discloses an inclined image plane accurate imaging transfer optical lens with a coupling telescope adapted to a DMD chip, and the optical lens comprises a transfer optical lens which is provided with a first lens, a second lens, a third bonding lens A, a third bonding lens B, a fourth bonding lens A, and a fourth bonding lens B which form a front lens unit. According to the transfer optical lens coupling telescope DMD inclined image plane imaging transfer optical lens, the design that an inclined optical axis is matched with the prism is adopted, and it is ensured that after light emitted by an image plane of an external lens is focused through the transfer lens, light emitted by the image plane of the external lens is focused by the transfer lens; the main light rays are incident to the inclined DMD image plane at the same angle, so that the angular deviation between the main light rays and the DMD normal is strictly limited, high-quality and uniform imaging is realized, and the imaging effect of a subsequent light path is ensured.

Description

Technical Field

[0001] This invention relates to the field of optical lens technology, specifically to a coupling telescope adapter DMD chip tilted image plane precision imaging relay optical lens. Background Technology

[0002] Digital micromirrors (DMDs), as high-speed, digitized spatial light modulators, have been widely used in high-speed cameras and digital lithography. In practical applications, the image from an external lens, such as a general-purpose lens or telescope, needs to be precisely imaged onto a DMD chip via a relay optical lens. Then, the image is modulated by the DMD and projected onto a CCD or CMOS sensor via a telecentric optical lens, achieving image modulation and encoding, thereby resolving ultra-high-speed moving objects beyond visual range, such as aircraft and missiles.

[0003] The DMD chip micromirror achieves light projection by deflecting at +12° / -12°. Imaging distant objects onto the DMD requires tilting the image plane of the intermediate imaging lens. However, the tilted image plane architecture presents a problem that is difficult to solve with traditional optical designs. This invention effectively solves this problem of optical design for observing distant objects.

[0004] Principal ray angle deviation: Traditional imaging systems require the principal ray axis to be perpendicular to the image plane. An tilted image plane will result in poor imaging quality at the edge of the field of view. This will not only cause uneven illumination, but will also seriously affect the efficiency and quality of the subsequent DMD modulation optical path, because the DMD micromirrors are extremely sensitive to the angle of incident light when they are deflected at +12° / -12°.

[0005] Severe asymmetric aberrations: The tilted image plane greatly disrupts the rotational symmetry of the system, introducing very severe astigmatism and coma, resulting in a sharp decline in image quality, especially in the resolution of the edge fields of view.

[0006] Digital micromirrors (DMDs), as core devices for high-speed, digital spatial light modulation, have been widely used in high-speed cameras, digital lithography, and other fields. In the image modulation process, an intermediate imaging lens projects the image of a distant external object onto the tilted image plane of the DMD, which then modulates the image before transmitting it to the sensor.

[0007] Most existing lenses are designed for planar image planes. When applied to the tilted image plane of a DMD with a resolution of 1280×720 and a pixel size of 5.4μm, the following drawbacks exist: 1. Severe aberrations and distortions: Aberrations in different areas of the tilted image plane cannot be corrected synchronously, resulting in blurred image edges, proportional distortion, and inability to match the DMD pixel array; 2. Low coupling efficiency: Light rays from long-distance, high-speed flying objects cannot be accurately incident on the DMD micro-image surface after passing through a traditional lens, resulting in wasted light energy. This can be achieved by coupling through this intermediate lens. 3. The design of a relay lens for coupling long focal length lenses to adapt to DMD tilted image plane imaging is quite difficult.

[0008] These problems severely restrict the application of DMD modulation systems. Therefore, there is an urgent need for a relay optical lens designed specifically for this type of tilted image plane imaging, while simultaneously achieving high uniformity, low astigmatism, and a flat image field to solve this problem in the existing technology.

[0009] Therefore, there is an urgent need for an improved technology to solve this problem in the existing technology. Summary of the Invention

[0010] The purpose of this invention is to provide a relay optical lens for coupling telescopes with DMD tilted image plane imaging. The relay optical lens adopts a design that combines a tilted optical axis with a prism, ensuring that the light rays emitted from the image plane of the external lens are focused by the relay lens and incident on the tilted DMD image plane at a consistent angle. This strictly limits the angular deviation between the principal ray and the DMD normal, which is a direct guarantee for achieving high-quality and uniform imaging, thus ensuring the imaging effect of subsequent optical paths. The coupling telescope is adapted to the DMD chip tilted image plane for precise imaging, with parameters such as the lens focal length and optical axis angle perfectly matched to the DMD chip, thereby solving the problems mentioned in the background art.

[0011] To achieve the above objectives, the present invention provides the following technical solution: a relay optical lens for precise imaging of tilted image plane of a coupling telescope with DMD chip, comprising a relay optical lens, wherein the relay optical lens includes a first lens, a second lens, a third cemented lens A, a third cemented lens B, a fourth cemented lens A, a fourth cemented lens B, a fifth filter, a sixth cemented lens A, a sixth cemented lens B, a seventh lens, an eighth lens, a ninth lens, a prism, and a DMD chip; The first lens, the second lens, the third cemented lens A, the third cemented lens B, the fourth cemented lens A, and the fourth cemented lens B constitute the front lens unit. The sixth cemented lens A, the sixth cemented lens B, the seventh lens, the eighth lens, the ninth lens, and the prism constitute the rear lens unit.

[0012] Preferably, the first lens, the second lens, the third cemented lens A, the third cemented lens B, the fourth cemented lens A, and the fourth cemented lens B constitute a front lens unit that converges the image of the external lens and then images it onto the tilted image plane of the DMD via a relay lens.

[0013] Preferably, the focal length of the relay optical lens is 1381.5mm, the angle between the optical axis and the normal of the DMD image plane is less than 45°, and the object side NA of the relay optical lens is 0.075.

[0014] Preferably, the DMD chip has a resolution of 1280×720, a pixel size of 5.4μm, and an imaging resolution of ≥90lp / mm (taking the monochromatic light 520-540nm band as an example).

[0015] Preferably, the front lens unit and the rear lens unit of the relay optical lens together form a combination of a concave lens and a convex lens.

[0016] Compared with the prior art, the beneficial effects of the present invention are: The relay optical lens coupling telescope's DMD tilted image plane imaging relay optical lens adopts a tilted optical axis and prism combination design, which ensures that the light rays emitted from the external lens image plane are focused by the relay lens and then incident on the tilted DMD image plane at a consistent angle. This strictly limits the angular deviation between the principal ray and the DMD normal, which is a direct guarantee for achieving high-quality and uniform imaging, thus ensuring the imaging effect of subsequent optical paths. The lens's focal length, optical axis angle and other parameters are fully matched with the DMD chip, and it can be directly integrated into high-speed cameras and digital lithography systems. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the optical lens structure for the inclined image plane imaging of the coupling telescope in this invention; Figure 2 This is a schematic diagram of the simulated light rays from the relay optical lens in the tilting image plane imaging of the coupling telescope of the present invention; Figure 3 This is a simulated MTF (Mean Transfer Function) data graph of the relay optical lens in the inclined image plane imaging of the coupling telescope of this invention; Figure 4 This is a simulated data diagram of the Spot array of optical lenses used for the inclined image plane imaging of the coupling telescope in this invention. Figure 5 This is a simulated FCD data diagram of the field curvature and distortion of the relay optical lens in the inclined image plane imaging of the coupled telescope of this invention.

[0018] In the diagram: 1. First lens; 2. Second lens; 3. Third cemented lens A; 4. Third cemented lens B; 5. Fourth cemented lens A; 6. Fourth cemented lens B; 7. Fifth filter; 8. Sixth cemented lens A; 9. Sixth cemented lens B; 10. Seventh lens; 11. Eighth lens; 12. Ninth lens; 13. Prism; 14. DMD chip; 15. Intermediate optical lens. Detailed Implementation

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] Please see Figures 1-5 This invention provides a technical solution: a relay optical lens for precise imaging of a DMD chip tilted image plane in a coupled telescope, comprising a relay optical lens 15, wherein the relay optical lens 15 includes a first lens 1, a second lens 2, a third cemented lens A3, a third cemented lens B4, a fourth cemented lens A5, a fourth cemented lens B6, a fifth filter 7, a sixth cemented lens A8, a sixth cemented lens B9, a seventh lens 10, an eighth lens 11, a ninth lens 12, a prism 13, and a DMD chip 14.

[0021] The first lens 1, the second lens 2, the third cemented lens A3, the third cemented lens B4, the fourth cemented lens A5, and the fourth cemented lens B6 constitute the front lens unit.

[0022] The sixth cemented lens A8, the sixth cemented lens B9, the seventh lens 10, the eighth lens 11, the ninth lens 12, and the prism 13 constitute the rear lens unit. The front lens unit and the rear lens unit on the intermediate optical lens 15 together form a combination of "concave lens + convex lens".

[0023] The first lens 1, the second lens 2, the third cemented lens A3, the third cemented lens B4, the fourth cemented lens A5, and the fourth cemented lens B6 constitute the front lens unit, which converges the image of the external lens and then images it onto the tilted image plane of the DMD through the intermediate lens.

[0024] The relay optical lens 15 has a focal length of 1381.5mm, and the angle between the optical axis and the normal of the DMD image plane is less than 45°. The object-side NA of the relay optical lens 15 is 0.075, and it is compatible with external general-purpose lenses and telescopes and other long focal length optical systems.

[0025] The DMD chip has 14 parameters: resolution of 1280×720, pixel size of 5.4μm, and imaging resolution ≥90lp / mm (taking monochromatic light 520-540nm band as an example).

[0026] The intermediate optical lens 15, through the front lens unit and the rear lens unit, controls the aberration within the monochromatic light band to within 0.03mm, meeting the imaging accuracy requirements of the DMD pixel size. After passing through the lens group, the light can be accurately projected onto the tilted image plane of the DMD.

[0027] The light rays from the image plane of the external lens first enter the front lens unit through the first lens 1, the second lens 2, the third cemented lens A3, the third cemented lens B4, the fourth cemented lens A5, and the fourth cemented lens B6. After initial convergence, the light passes through the aperture adjustment stop and the fifth filter 7. Subsequently, the light enters the rear lens unit through the sixth cemented lens A8, the sixth cemented lens B9, the seventh lens 10, the eighth lens 11, and the ninth lens 12. After the prism 13 corrects for aberrations, the light is projected onto the tilted image plane 14 of the DMD chip at an incident angle of less than 45°, forming a clear and distortion-free image of the object.

[0028] In this embodiment, the imaging resolution of the relay optical lens 15 reaches 90 lp / mm, which fully matches the resolution requirement of the DMD chip 1280×720, and the light can accurately cover the DMD micromirror area.

[0029] Table 1

[0030] Table 2

[0031] Table 3

[0032] The relay optical lens 15, which is a coupling telescope DMD tilted image plane imaging relay optical lens, adopts a tilted optical axis and prism combination design to ensure that the light rays emitted from the image plane of the external lens are focused by the relay lens and then incident on the tilted DMD image plane at a consistent angle. This strictly limits the angular deviation between the principal ray and the DMD normal, which is a direct guarantee for achieving high-quality and uniform imaging, thus ensuring the imaging effect of subsequent optical paths. The lens's focal length, optical axis angle and other parameters are fully matched with the DMD chip, and it can be directly integrated into high-speed cameras and digital lithography systems.

[0033] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A relay optical lens for precise imaging of tilted image plane of a coupled telescope with DMD chip, comprising a relay optical lens (15), characterized in that: The intermediate optical lens (15) includes a first lens (1), a second lens (2), a third cemented lens A (3), a third cemented lens B (4), a fourth cemented lens A (5), a fourth cemented lens B (6), a fifth filter (7), a sixth cemented lens A (8), a sixth cemented lens B (9), a seventh lens (10), an eighth lens (11), a ninth lens (12), a prism (13), and a DMD chip (14). The first lens (1), the second lens (2), the third cemented lens A (3), the third cemented lens B (4), the fourth cemented lens A (5), and the fourth cemented lens B (6) constitute the front lens unit; The sixth cemented lens A (8), the sixth cemented lens B (9), the seventh lens (10), the eighth lens (11), the ninth lens (12), and the prism (13) constitute the rear lens unit.

2. The optical relay lens for precise imaging of tilted image plane of a coupled telescope adapted to a DMD chip as described in claim 1, characterized in that: The first lens (1), the second lens (2), the third cemented lens A (3), the third cemented lens B (4), the fourth cemented lens A (5), and the fourth cemented lens B (6) constitute the front lens unit, which converges the image of the external lens and then images it onto the tilted image plane of the DMD through the intermediate lens.

3. The optical relay lens for precise imaging of tilted image plane of a coupled telescope adapted to a DMD chip as described in claim 1, characterized in that: The focal length of the relay optical lens (15) is 1381.5mm, the angle between the optical axis and the normal of the DMD image plane is less than 45°, and the object-side NA of the relay optical lens (15) is 0.

075.

4. The optical relay lens for precise imaging of tilted image plane of a coupled telescope adapted to a DMD chip as described in claim 1, characterized in that: The DMD chip (14) has a resolution of 1280×720, a pixel size of 5.4μm, and an imaging resolution of ≥90lp / mm (taking the monochromatic light 520-540nm band as an example).

5. The optical relay lens for precise imaging of tilted image plane of a coupled telescope adapted to a DMD chip as described in claim 1, characterized in that: The front lens unit and the rear lens unit of the intermediate optical lens (15) together form a combination of "concave lens + convex lens".

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