Continuous zooming active transparent window optical system based on narrow-band filtering

Abstract

The invention belongs to the technical field of optical detection, and particularly relates to a narrow-band filter-based continuous zooming active window-penetrating optical system, which comprises a semiconductor laser, a CCD (Charge Coupled Device) detector, a variable beam scattering emission assembly and a variable view field detection assembly provided with a narrow-band filter, laser emitted by the semiconductor laser is subjected to coupling and beam expanding through the variable-beam scattering and emitting assembly to irradiate a window-penetrating area, the semiconductor laser continuously irradiates a target object in the window-penetrating area, and scattered light and reflected light of the target object are transmitted to the variable-view-field detection assembly through the atmosphere. And the information of the target object passes through the narrow-band optical filter and finally reaches a CCD (Charge Coupled Device) detector. Day and night reconnaissance of important targets in the dark environment in the window can be achieved, meanwhile, the near-infrared band is adopted, concealment is considered, backward scattering is restrained based on narrow-band filtering and view field switching, and day and night dual purposes are achieved through power adjustability and continuous zooming.

Description

Technical Field

[0001] The present invention belongs to the technical field of optical detection, and in particular, relates to a continuously variable magnification active window optical system based on narrow-band filtering. Background Art

[0002] With the vigorous development of optoelectronic equipment, optoelectronic technology, and display technology in terms of integration, intelligent control, and multi-technology and multi-field collaboration and integration, the detection and reconnaissance of information inside windows has become urgent. The research on through-window imaging technology is of great significance in the fields of optoelectronic detection, security monitoring, traffic evidence collection, military reconnaissance, urban warfare, and unmanned warfare.

[0003] When working around the clock in special environments such as optoelectronic reconnaissance, public security intelligence, security monitoring, and urban warfare, it is necessary not only to accurately obtain important target information in the dark environment inside the window (car window or optoelectronic window), but also to ensure that other targets inside the window are not exposed or that the target information is not discovered by the other party when being reconnaissance. At present, traditional monitoring security or through-window imaging technology has certain disadvantages and poor actual use effect. For example, it is impossible to see through the window during the day, strong flashes interfere with drivers, it is greatly affected by ambient light, and image information is lost.

[0004] Therefore, those skilled in the art are in urgent need of developing a continuously variable magnification active window optical system based on narrow-band filtering to address the disadvantages of current traditional surveillance and security or window imaging technologies. Summary of the invention

[0005] The purpose of the present invention is to provide a continuously variable magnification active window optical system based on narrow-band filtering, which can realize day and night reconnaissance of important targets in a dark environment inside the window, while taking into account concealment by using the near-infrared band, suppressing backscattering based on narrow-band filtering and field of view switching, and achieving day and night use through adjustable power and continuous magnification.

[0006] In order to achieve the above-mentioned object of the invention, the present invention proposes the following technical solutions:

[0007] A continuously variable magnification active window optical system based on narrowband filtering comprises a semiconductor laser, a CCD detector, a variable beam dispersion emission component and a variable field of view detection component provided with a narrowband filter. The laser emitted by the semiconductor laser is coupled and expanded by the variable beam dispersion emission component to illuminate a window area, and the semiconductor laser continuously illuminates a target object in the window area. The scattered light and reflected light of the target object are transmitted through the atmosphere to reach the variable field of view detection component, and the information of the target object finally reaches the CCD detector through the narrowband filter.

[0008] Preferably, the semiconductor laser uses a semiconductor laser with a wavelength of 808nm±3nm at 25℃±5℃, and the semiconductor laser is temperature compensated by a TEC temperature controller, and the temperature is controlled at 60℃±5℃, so that the emission wavelength of the semiconductor laser is controlled at 820nm±10nm.

[0009] Preferably, the variable beam divergence emission component has an operating band of 820 nm, a magnification ratio of 22.6X, an illumination beam divergence angle variation range of 0.2° to 4.5°, and an overall size of Φ32 mm×87 mm.

[0010] Preferably, the operating spectrum range of the variable field of view detection component is 0.81 μm to 0.83 μm, the magnification ratio is 13.6X, the field of view is 7.3°×5.5° to 0.54°×0.4°, and the overall size is Φ70mm×150mm.

[0011] Preferably, the variable beam dispersion emission assembly adopts a three-element zoom optical structure, including lens 1, lens 2, lens 3, lens 4, lens 5 and window 1, wherein lens 1 and lens 2 constitute component 1A, component 1A is compensation group A, lens 3 constitutes component 2A, component 2A is variable magnification group A, lens 4 and lens 5 constitute component 3A, component 3A is rear fixed group A; the variable beam dispersion emission assembly controls the radial size of the variable beam dispersion emission assembly by controlling the exit pupil position at one end of compensation group A, and reduces the amount of off-axis vignetting. This solution can fully guarantee the laser utilization rate and spot quality, and is conducive to controlling the volume size of the continuous variable magnification active window optical system.

[0012] Preferably, the variable field of view detection assembly adopts a four-component zoom optical structure, including window two, lens six, lens seven, lens eight, lens nine, lens ten, lens eleven, lens twelve, lens thirteen, lens fourteen, a narrow-band filter, lens fifteen and lens sixteen; the window two, lens six and lens seven constitute component one B, and component one B is a front fixed group; the lens eight, lens nine and lens ten constitute component two B, and component two B is a variable magnification group B; the lens eleven, lens twelve and lens thirteen constitute component three B, and component three B is a compensation group B; the lens fourteen, narrow-band filter, lens fifteen and lens sixteen constitute component four, and component four is a rear fixed group B; the variable field of view detection assembly controls the radial size of the variable field of view detection assembly by controlling the position of the variable aperture to be located at the maximum radial size position of the variable field of view detection assembly; the narrow-band filter is controlled at a position where the incident light vector height is the smallest and the light is the smoothest, thereby reducing the amount of off-axis vignetting. This solution can fully guarantee the light energy and imaging quality, and is conducive to controlling the length and weight of the continuous zoom active window optical system.

[0013] Preferably, the narrowband filter is made of HB720 filter glass and coated with 820nm narrowband filter film. The transmission area of ​​the narrowband filter is 810nm-830nm, and the average transmittance is not less than 90%. Considering the stability of the narrowband filter, the efficiency of suppressing backscattered light, the aberration introduced to the detection component, etc., the incident angle of the incident light should not be too large; and the size and weight of the narrowband filter are controlled by controlling the incident light vector height of the narrowband filter.

[0014] Preferably, the narrow-band filter is located between lens fourteen and lens fifteen of the variable field of view detection assembly, and the incident angle of light of the narrow-band filter is controlled to be no greater than 5° and the vector height is no greater than 8 mm.

[0015] Preferably, the dynamic response range of the CCD detector is 68 dB (ie, between 0 and 68 dB), and the quantum response rate in the wavelength range of 0.82 μm is not less than 49%.

[0016] The present invention also includes other devices or components that can enable the continuous variable magnification active window optical system based on narrow-band filtering to operate normally, all of which are conventional technical means in the field. In addition, devices or components not limited in the present invention all adopt conventional means in the prior art.

[0017] Compared with the prior art, the present invention has the following advantages:

[0018] The present invention can realize day and night reconnaissance of important targets in dark environments inside windows. At the same time, it uses near-infrared bands to take into account concealment, suppresses backscattering based on narrow-band filtering and field of view switching, and realizes day and night use through adjustable power and continuous magnification. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0020] Figure 1 An optical system diagram of a continuously variable magnification active window optical system based on narrow-band filtering in an embodiment of the present invention.

[0021] Figure 2 Schematic diagram of the optical structure of the embodiment of the present invention when the illumination beam divergence angle is 0.2° and the CCD detector field of view is 0.54°×0.4° at the telephoto end small field of view.

[0022] Figure 3 Schematic diagram of the optical structure of the embodiment of the present invention when the illumination beam divergence angle is 4.5° and the CCD detector field of view is 7.3°×5.5° at the short-focus end and large field of view.

[0023] In the figure: 1-1 semiconductor laser, 2-1 lens one, 2-2 lens two, 2-3 lens three, 2-4 lens four, 2-5 lens five, 2-6 window one, 3-1 window two, 3-2 lens six, 3-3 lens seven, 3-4 lens eight, 3-5 lens nine, 3-6 lens ten, 3-7 lens eleven, 3-8 lens twelve, 3-9 lens thirteen, 3-10 lens fourteen, 3-11 lens fifteen, 3-12 lens sixteen, 4-1 narrow band filter, 5-1 CCD detector. DETAILED DESCRIPTION

[0024] The present invention is described clearly below in conjunction with the drawings and specific embodiments in the embodiments of the present invention. The description herein is only used to explain the present invention, but is not intended to limit the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work, any modifications, equivalent substitutions, improvements, etc., should be included in the protection scope of the present invention.

[0025] Example

[0026] like Figures 1 to 3 As shown, this embodiment is a continuously variable magnification active window optical system based on narrowband filtering, comprising a semiconductor laser 1-1, a CCD detector 5-1, a variable beam dispersion emission component and a variable field of view detection component provided with a narrowband filter 4-1. The laser emitted by the semiconductor laser 1-1 is coupled and expanded by the variable beam dispersion emission component to illuminate the window area, and the semiconductor laser 1-1 continuously illuminates the target object in the window area. The scattered light and reflected light of the target object are transmitted through the atmosphere to reach the variable field of view detection component, and the information of the target object finally reaches the CCD detector 5-1 through the narrowband filter 1-1.

[0027] Specifically, the wavelength selection of the semiconductor laser 1-1 is mainly based on factors such as human eye safety, the QE response rate of the CCD detector 5-1, the TEC operating temperature range, and the system volume cost. In this embodiment, a semiconductor laser with a wavelength of 808nm±3nm at 25℃±5℃ is used, and the semiconductor laser 1-1 is temperature compensated by a TEC temperature controller to reduce the influence of laser temperature drift, and the temperature is controlled at 60℃±5℃, so that the emission wavelength of the semiconductor laser 1-1 is controlled at 820nm±10nm.

[0028] In this embodiment, the variable beam dispersion emission assembly adopts a three-element zoom optical structure, including lens 1 2-1, lens 2-2, lens 3 2-3, lens 4 2-4, lens 5 2-5 and window 1 2-6, wherein the lens 1 2-1 and lens 2 2-2 constitute component 1 A, which is a compensation group A, the lens 3 2-3 constitutes component 2 A, which is a variable magnification group A, the lens 4 2-4 and lens 5 2-5 constitute component 3 A, which is a rear fixed group A; the variable beam dispersion emission assembly controls the radial size of the variable beam dispersion emission assembly by controlling the exit pupil position at one end of the compensation group A, thereby reducing the amount of off-axis vignetting. This solution can fully guarantee the laser utilization rate and the quality of the light spot, and is conducive to controlling the volume size of the continuous variable magnification active window optical system. The working band of the variable beam divergence emission component is 820nm, the magnification ratio is 22.6X, the irradiation beam divergence angle range is 0.2°~4.5°, the overall size is Φ32mm×87mm, and the detailed structural parameters of its optical system are shown in Table 1.

[0029] Table 1 Structural parameters of three-component zoom optical structure

[0030]

[0031]

[0032] In this embodiment, the variable field of view detection component adopts a four-component zoom optical structure, including window two 3-1, lens six 3-2, lens seven 3-3, lens eight 3-4, lens nine 3-5, lens ten 3-6, lens eleven 3-7, lens twelve 3-8, lens thirteen 3-9, lens fourteen 3-10, narrow band filter 4-1, lens fifteen 3-11 and lens sixteen 3-12; the window two 3-1, lens six 3-2, lens seven 3-3 constitute component one B, the component one B is a front fixed group, the lens eight 3-4, lens nine 3-5, lens ten 3-6 constitute component two B, the component The second B is a variable magnification group B, the lens eleven 3-7, the lens twelve 3-8, and the lens thirteen 3-9 constitute the component three B, the component three B is the compensation group B, the lens fourteen 3-10, the narrow band filter 4-1, the lens fifteen 3-11, and the lens sixteen 3-12 constitute the component four, and the component four is the rear fixed group B. The variable field detection component is located at the maximum radial size position of the variable field detection component by controlling the position of the variable diaphragm to control the radial size of the variable field detection component, and the narrow band filter 4-1 is controlled at the position where the incident light vector height is the smallest and the light is the most gentle, reducing the amount of off-axis vignetting. This solution can fully guarantee the light energy and imaging quality, and is conducive to controlling the length and weight of the continuous variable magnification active window optical system. The working spectrum range of the variable field of view detection assembly is 0.81 μm to 0.83 μm, the zoom ratio is 13.6X, the field of view is 7.3°×5.5° to 0.54°×0.4°, and the overall size is Φ70mm×150mm. Please refer to Table 2 for detailed structural parameters of its optical system.

[0033] Table 2 Structural parameters of the four-element zoom optical structure

[0034]

[0035]

[0036]

[0037] More specifically, the material of the narrowband filter 4-1 is HB720 filter glass, and is coated with an 820nm narrowband filter film. The transmission area of ​​the narrowband filter 4-1 is 810nm~830nm, and the average transmittance is not less than 90%. Considering the stability of the narrowband filter 4-1, the efficiency of suppressing backscattered light, the aberration introduced to the detection component, etc., the incident angle of the incident light should not be too large; and by controlling the size of the incident light vector height of the narrowband filter 4-1, the size and weight of the narrowband filter 4-1 are controlled. In this embodiment, the narrowband filter 4-1 is located between the lens fourteen 3-10 and the lens fifteen 3-11 of the variable field of view detection component, and the incident angle of the narrowband filter 4-1 is controlled to be no more than 5°, and the vector height is no more than 8mm.

[0038] In this embodiment, the dynamic response range of the CCD detector 5-1 is 68dB (i.e., between 0 and 68dB), and the quantum response rate in the wavelength range of 0.82μm is not less than 49% (relative value). The CCD detector 5-1 has a high spatial resolution, a sufficient dynamic gain range, and a high quantum efficiency to meet the through-window detection range of different contrast environments.

[0039] The embodiments of the present invention have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.

Claims

1. A continuously variable active window optical system based on narrow-band filtering, comprising a semiconductor laser and a CCD detector, characterized in that: It also includes a variable beam dispersion emission component and a variable field of view detection component provided with a narrow-band filter. The laser emitted by the semiconductor laser is coupled and expanded by the variable beam dispersion emission component to illuminate the window area, and the semiconductor laser continuously illuminates the target object in the window area. The scattered light and reflected light of the target object are transmitted through the atmosphere to reach the variable field of view detection component, and the information of the target object finally reaches the CCD detector through the narrow-band filter.

2. The continuously variable active window optical system based on narrow-band filtering according to claim 1, characterized in that: The semiconductor laser has a wavelength of 808nm±3nm at 25°C±5°C, and the semiconductor laser is temperature compensated by a TEC temperature controller, and the temperature is controlled at 60°C±5°C, so that the emission wavelength of the semiconductor laser is controlled at 820nm±10nm.

3. The continuously variable active window optical system based on narrow-band filtering according to claim 2, characterized in that: The variable beam divergence emission component has an operating band of 820 nm, a zoom ratio of 22.6X, an illumination beam divergence angle variation range of 0.2° to 4.5°, and an overall size of Φ32 mm×87 mm.

4. The continuously variable active window optical system based on narrow-band filtering according to claim 3, characterized in that: The variable field of view detection component has an operating spectrum range of 0.81 μm to 0.83 μm, a magnification ratio of 13.6X, a field of view of 7.3°×5.5° to 0.54°×0.4°, and an overall size of Φ70 mm×150 mm.

5. The continuously variable active window optical system based on narrow-band filtering according to claim 3, characterized in that: The variable beam divergence emission assembly adopts a three-component zoom optical structure, including lens one, lens two, lens three, lens four, lens five and window one, wherein lens one and lens two constitute component one A, component one A is compensation group A, lens three constitutes component two A, component two A is variable magnification group A, lens four and lens five constitute component three A, component three A is rear fixed group A; the variable beam divergence emission assembly controls the radial size of the variable beam divergence emission assembly by controlling the exit pupil position to be located at one end of compensation group A, thereby reducing the amount of off-axis vignetting.

6. The continuously variable active window optical system based on narrow-band filtering according to claim 4, characterized in that: The dynamic response range of the CCD detector is 68 dB, and the quantum response rate in the wavelength range of 0.82 μm is not less than 49%.

7. The continuously variable active window optical system based on narrow-band filtering according to claim 4, characterized in that: The variable field of view detection component adopts a four-component zoom optical structure, including window two, lens six, lens seven, lens eight, lens nine, lens ten, lens eleven, lens twelve, lens thirteen, lens fourteen, a narrow-band filter, lens fifteen and lens sixteen; the window two, lens six and lens seven constitute component one B, and component one B is a front fixed group; the lens eight, lens nine and lens ten constitute component two B, and component two B is a variable magnification group B; the lens eleven, lens twelve and lens thirteen constitute component three B, and component three B is a compensation group B; the lens fourteen, narrow-band filter, lens fifteen and lens sixteen constitute component four, and component four is a rear fixed group B; the variable field of view detection component is located at the maximum radial size position of the variable field of view detection component by controlling the position of the variable diaphragm to control the radial size of the variable field of view detection component; the narrow-band filter is controlled at a position where the incident light vector height is the smallest and the light is the gentlest, thereby reducing the amount of off-axis vignetting.

8. The continuously variable magnification active window optical system based on narrow-band filtering according to claim 7, characterized in that: The narrow-band filter is made of HB720 filter glass and coated with 820nm narrow-band filter film. The transmission area of ​​the narrow-band filter is 810nm-830nm, and the average transmittance is not less than 90%.

9. The continuously variable magnification active window optical system based on narrow-band filtering according to claim 8, characterized in that: The narrow-band filter is located between lens fourteen and lens fifteen of the variable field of view detection assembly, and the incident angle of light of the narrow-band filter is controlled to be no greater than 5° and the sag height is controlled to be no greater than 8 mm.

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