Pulse laser glass-permeable and film-permeable imager

Abstract

The utility model discloses a pulse laser glass-permeable and film-permeable imager, which comprises a laser module, a gating imaging device and a main control board, and is characterized in that the laser module is configured to generate pulse laser to irradiate a target to be measured; the gated imaging device is configured to receive the pulse laser reflected by the target to be measured; and the main control board processes the to-be-detected target image generated by the gating imaging device. The high penetrability of the nanosecond pulse laser light source is utilized, the gated imaging device has a gated gating function, the nanosecond pulse laser and the gated imaging device are synchronized, and a narrow gating shutter is selected to carry out space slicing on different distances, so that the interference of the environment before and after a target object is reduced, and the imaging accuracy is improved. Therefore, the influence of most back scattering light on system imaging is inhibited, the resolution ratio and the signal-to-noise ratio of the system are greatly improved, a clear and distinguishable high-contrast imaging picture is obtained, and glass-penetrating (window-penetrating) film-penetrating imaging of a target object in a vehicle is realized.

Description

Technical Field

[0001] The utility model relates to the technical field of optoelectronic imaging, in particular to a pulsed laser imaging device for penetrating glass and film. Background Art

[0002] Optoelectronic imaging systems are widely used in the fields of monitoring, detection, etc. due to their excellent concealment. However, passive imaging systems such as ordinary imaging devices (cameras, surveillance cameras, etc.) are easily affected by ambient light (strong light, backlight, weak light, no light) and bad weather (rain, snow, fog, haze, smoke), and cannot clearly record the characteristics of the target to be measured. For example, during traffic control, it is necessary to photograph the people in the car to understand the situation of the people in the car (whether overcrowded, whether wearing seat belts, whether carrying dangerous goods). However, ordinary imaging devices cannot clearly record and observe the target to be measured through media such as glass and film under complex ambient light conditions or in harsh environments.

[0003] Patent application CN202210498436.2 discloses a new type of infrared imaging device for penetrating glass and film, including a camera and a supplementary light; the camera includes a band-pass filter A, a lens, a detector and an image transmission module arranged in sequence, and the detector is electrically connected to the image transmission module; the supplementary light includes a band-pass filter B, a gas discharge lamp and a trigger circuit module arranged in sequence, and the gas discharge lamp is electrically connected to the trigger circuit module. The working principle of this camera: the infrared light with a wavelength range of 750-900nm emitted by the supplementary light penetrates the film-coated glass and is reflected by the human body in the car, and the light beam that penetrates the film-coated glass for the second time and enters the camera is beam A; the infrared light with a wavelength of 750-900nm in the ambient sunlight directly reflected by the film-coated glass enters the camera as beam B; the infrared light with a wavelength range of 750-900nm of the supplementary light directly reflected by the film-coated glass enters the camera as beam C; when the intensity of beam A is greater than the intensity of beam B + C, high-definition imaging of the people in the car through the glass and film is achieved. However, in a complex environment (rain, snow, fog, haze, smoke), since the light will be weakened in such media, it is easy to occur that the intensity of beam A that penetrates the film-coated glass for the second time and enters the camera cannot be greater than the intensity of beam B + C, so that clear imaging of the people in the car cannot be performed. Summary of the Utility Model

[0004] The purpose of the utility model is to provide a pulsed laser imaging device for penetrating glass and film to solve the problems of low imaging resolution of existing imaging devices. This imaging device can penetrate glass (window) and film, detect various targets in the car, and is not affected by ambient light (strong light, backlight, weak light, no light) and bad weather (rain, snow, fog, haze, smoke), and has high imaging resolution.

[0005] The purpose of the utility model is achieved by the following technical solutions:

[0006] A pulsed laser glass and film imager, comprising:

[0007] A laser module configured to generate pulsed laser light for irradiating a target to be measured; the laser module includes a nanosecond pulsed laser device and a collimator, and the nanosecond pulsed laser device is connected to the collimator through an optical fiber;

[0008] A gated imaging device configured to receive the pulsed laser light reflected by the target to be measured; the gated imaging device includes a filter, an imaging lens, and a GCMOS camera, and the GCMOS camera includes a CMOS chip, a gating module, and a timing synchronization module. The gating module is connected to the CMOS chip through a signal trigger line and controls the opening time and exposure time of the CMOS chip; the timing synchronization module is connected to the nanosecond pulsed laser device and the CMOS chip through signal trigger lines for timing synchronization; the laser module and the gated imaging device are connected through signal trigger lines;

[0009] A main control board configured to process the image of the target to be measured generated by the gated imaging device.

[0010] Further, the filter is a narrowband filter and its central wavelength is the same as the central wavelength of the nanosecond pulsed laser device.

[0011] Further, the full width at half maximum of the wavelength of the pulsed laser light generated by the nanosecond pulsed laser device is less than the full width at half maximum of the central wavelength of the filter.

[0012] Further, the wavelength range of the pulsed laser light generated by the nanosecond pulsed laser device includes 700 - 900 nm.

[0013] Further, the output pulse width range of the pulsed laser light generated by the nanosecond pulsed laser device includes 15 - 200 ns.

[0014] Further, the output laser type of the nanosecond pulsed laser device is pulsed, and its output pulse width is less than or equal to the exposure time.

[0015] Further, the connection manner between the filter and the imaging lens includes: the filter is disposed in front of the imaging lens.

[0016] Further, the connection manner between the filter and the imaging lens includes: the filter is disposed behind the imaging lens.

[0017] Further, the connection manner between the filter and the imaging lens includes: the filter is disposed both in front of and behind the imaging lens.

[0018] The beneficial effects of the present utility model are as follows:

[0019] The present utility model utilizes the high penetration of the nanosecond pulsed laser light source and the gating function of the gated imaging device. By synchronizing the nanosecond pulsed laser with the gated imaging device and selecting a narrow gating shutter for spatial slicing at different distances, the interference from the front and rear environments of the target object is reduced, thereby suppressing the influence of most backscattered light on the system imaging, greatly improving the resolution and signal-to-noise ratio of the system, and obtaining a clear and distinguishable high-contrast imaging diagram. This utility model can also achieve imaging through glass (windows) and membranes of in-vehicle target objects under strong light, backlight, weak light or even no light conditions, as well as in harsh weather such as rain, snow, fog, haze, and smoke, and can be widely applied in fields such as security monitoring. Description of the Drawings

[0020] Figure 1 is a schematic structural diagram of a pulsed laser imaging device through glass and membrane;

[0021] Figure 2 is another schematic structural diagram of a pulsed laser imaging device through glass and membrane.

[0022] Description of the reference numerals: 1 - nanosecond pulsed laser device; 2 - optical fiber; 3 - collimator; 4 - filter; 5 - imaging lens; 6 - GCMOS camera; 61 - CMOS chip; 62 - gating module; 63 - timing synchronization module; 7 - main control board; 8 - housing. Detailed Embodiments

[0023] For a clearer understanding of the technical features, objectives, and effects of the present utility model, the detailed embodiments of the present utility model are now described. It should be understood that the specific embodiments described herein are only used to explain the present utility model and are not used to limit the present utility model, that is, the described embodiments are only a part of the embodiments of the present utility model, rather than all of the embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative efforts fall within the scope of protection of the present utility model.

[0024] As Figure 1 - Figure 2 shown, the present utility model provides a pulsed laser imaging device through glass and membrane, including a laser module, a gated imaging device, and a main control board 7. The laser module is configured to generate pulsed laser light and irradiate it onto the target to be measured; the laser module includes a nanosecond pulsed laser device 1 and a collimator 3, and the nanosecond pulsed laser device 1 is connected to the collimator 3 through an optical fiber 2.

[0025] The gated imaging device is configured to receive pulsed laser light reflected by the target to be measured; the gated imaging device includes a filter 4, an imaging lens 5, and a GCMOS camera 6. The filter 4 can be installed in front of or behind the imaging lens 5 in a set. Preferably, the filter 4 can be installed in front of and behind the imaging lens 5 in a set each, as long as it can effectively filter ambient stray light. From a practical application perspective, the signal (laser reflected light) will attenuate by 10 - 50% each time it passes through the filter 4, while the noise (other stray light) will be reduced by 99.99% each time it passes through the filter 4 (roughly calculated with the filter cut-off depth OD = 4). At different noise levels, the benefit of increasing the signal-to-noise ratio can be estimated. The GCMOS camera 6 includes a CMOS chip 61, a gating module 62, and a timing synchronization module 63. The gating module 62 is connected to the CMOS chip 61 through a signal trigger line and controls the opening time and exposure time of the CMOS chip 61; the timing synchronization module 63 is connected to the nanosecond pulsed laser device 1 and the CMOS chip 61 through signal trigger lines for timing synchronization. The laser module and the gated imaging device are connected through signal trigger lines.

[0026] The main control board 7 is configured to process the image of the target to be measured generated by the gated imaging device.

[0027] To achieve a better imaging effect, the filter 4 is a narrowband filter and the central wavelength of the filter 4 is the same as the central wavelength of the nanosecond pulsed laser device 1.

[0028] To achieve a better imaging effect, the full width at half maximum of the wavelength of the pulsed laser generated by the nanosecond pulsed laser device 1 is less than the full width at half maximum of the central wavelength of the filter 4.

[0029] To achieve a better imaging effect, the wavelength of the illumination light source provided by the nanosecond pulsed laser device 1 to the target to be measured is preferably 700 - 900 nm, such as 700 nm, 750 nm, 850 nm, 860 nm, 900 nm.

[0030] To achieve a better imaging effect, the output pulse width of the illumination light source provided by the nanosecond pulsed laser device 1 to the target to be measured is 15 ns - 200 ns, such as 15 ns, 50 ns, 100 ns, 150 ns, 200 ns. In the present utility model, the timing synchronization module 63 is used to control the opening time of the nanosecond pulsed laser device 1 and the synchronization of the timing of the CMOS chip 61, so as to achieve the shooting of the target to be measured inside the vehicle. Since only the information of the required imaging area is collected, precise detection imaging at different distances and different depths of field can be achieved.

[0031] Application scenario 1 test:

[0032] At the entrance and exit of a certain unit, the in-vehicle personnel of passing vehicles were photographed using a color high-definition camera and the pulsed laser through-glass and through-film imager of the present utility model respectively at the same time and in the same environment (noon, backlit shooting). According to Figure 1 Install the equipment according to the structure, set the height of the tripod to 140 cm, and make the optical axis of the pulsed laser generated by the nanosecond pulsed laser device 1 parallel to the road where the vehicle to be tested is traveling. At the same time, in order to achieve a better imaging effect, the illumination direction of the nanosecond pulsed laser device 1 is the lowest speed point where the vehicle to be tested enters and exits from the entrance and exit. It can be seen from the shooting results that an ordinary camera cannot take high-definition images of the in-vehicle personnel through the car window, while the pulsed laser through-glass and through-film imager provided by the present utility model can penetrate the window to obtain high-definition images of the in-vehicle personnel, meeting the conditions for identifying the personnel situation.

[0033] Application scenario 2 test:

[0034] At the entrance and exit of a certain unit, the in-vehicle personnel of passing vehicles were photographed using a color high-definition camera and the pulsed laser through-glass and through-film imager of the present utility model respectively at the same time and in the same environment (rainy day shooting). According to Figure 2 Install the equipment according to the structure, set the height of the tripod to 140 cm, and make the optical axis of the pulsed laser generated by the nanosecond pulsed laser device 1 parallel to the road where the vehicle to be tested is traveling. At the same time, in order to achieve a better imaging effect, the illumination direction of the nanosecond pulsed laser device 1 is the lowest speed point where the vehicle to be tested enters and exits from the entrance and exit. It can be seen from the shooting results that an ordinary camera cannot take high-definition images of the in-vehicle personnel through the car window, while the pulsed laser through-glass and through-film imager provided by the present utility model can penetrate the window to obtain high-definition images of the in-vehicle personnel, meeting the conditions for identifying the personnel situation.

[0035] The above are only the preferred embodiments of the present utility model. It should be understood that the present utility model is not limited to the form disclosed herein, should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be changed within the scope of the concept described herein through the above teachings or the techniques or knowledge in related fields. And any changes and modifications made by those skilled in the art without departing from the spirit and scope of the present utility model shall fall within the protection scope of the appended claims of the present utility model.

Claims

1. A pulsed laser through-glass and through-film imager, characterized in that: include: A laser module is configured to generate a pulsed laser to irradiate a target to be measured; the laser module comprises a nanosecond pulse laser device and a collimator, and the nanosecond pulse laser device is connected to the collimator via an optical fiber; A gated imaging device is configured to receive a pulsed laser reflected by a target to be measured; the gated imaging device comprises a filter, an imaging lens and a GCMOS camera, the GCMOS camera comprises a CMOS chip, a gate control module and a timing synchronization module, the gate control module is connected to the CMOS chip via a signal trigger line and controls the start time and exposure time of the CMOS chip; the timing synchronization module is connected to the nanosecond pulse laser device and the CMOS chip via a signal trigger line for timing synchronization; the laser module and the gated imaging device are connected via a signal trigger line; The main control board is configured to process the image of the target to be measured generated by the gated imaging device.

2. The pulse laser through-glass and through-film imager according to claim 1, characterized in that: The filter is a narrow-band filter and its central wavelength is consistent with the central wavelength of the nanosecond pulse laser device.

3. The pulse laser through-glass and through-film imager according to claim 1, characterized in that: The half-width at half maximum of the wavelength of the pulsed laser generated by the nanosecond pulsed laser device is smaller than the half-width at half maximum of the central wavelength of the filter.

4. The pulse laser through-glass and through-film imager according to claim 1, characterized in that: The wavelength of the pulse laser generated by the nanosecond pulse laser device ranges from 700 to 900 nm.

5. The pulse laser through-glass and through-film imager according to claim 1, characterized in that: The output pulse width of the pulse laser generated by the nanosecond pulse laser device ranges from 15 to 200 ns.

6. The pulse laser through-glass and through-film imager according to claim 1, characterized in that: The nanosecond pulse laser device outputs a pulsed laser, and its output pulse width is less than or equal to the exposure time.

7. The pulse laser through-glass and through-film imager according to claim 1, characterized in that: The connection method of the optical filter and the imaging lens includes: the optical filter is arranged in front of the imaging lens.

8. The pulse laser through-glass and through-film imager according to claim 1, characterized in that: The connection method of the optical filter and the imaging lens includes: the optical filter is arranged behind the imaging lens.

9. The pulse laser through-glass and through-film imager according to claim 1, characterized in that: The connection method of the optical filter and the imaging lens includes: the optical filter is arranged in front of and behind the imaging lens at the same time.

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