CN112911172B - Apparatus and method for distance extraction of target scene based on InGaAs camera - Google Patents

Abstract

The invention discloses a target scene distance extraction device based on an InGaAs camera, which comprises a laser, a time sequence control and image acquisition processing module, a transmitting lens, a receiving lens and the InGaAs camera, and also discloses a target scene distance extraction method based on the InGaAs camera. The invention adopts a high-precision time delay and image difference method, can effectively extract a distance value while extracting a target scene, and the distance precision can be matched with an internal clock of a camera to achieve a pixel integral counting clock. The invention solves the problem that the laser gating imaging precision is limited by the minimum integration time of the device.

Description

Object scene distance extraction device and method based on InGaAs camera

technical field

The invention relates to the field of photoelectric detection, in particular to an InGaAs camera-based target scene distance extraction device, and also to an InGaAs camera-based target scene distance extraction method, which is suitable for high-precision target scene distance extraction.

Background technique

The development of optoelectronic technology has promoted the rapid development of optoelectronic passive observation equipment, and promoted the wide application of passive observation equipment based on visible light imaging, short-wave infrared imaging, and mid-far infrared imaging in national defense, military, security and defense. However, passive imaging It is difficult to obtain the distance value of the target area. Laser active imaging technology represented by lidar can quickly obtain the target distance value and develop rapidly, but its imaging speed and imaging detail resolution are not as good as passive imaging, which results in the advantages of both. Combined with the volume laser gating imaging technology, it can not only obtain the details of the target, but also obtain the distance value of the target area.

Existing laser range gating methods are limited by the spectral response and integration time of imaging devices. Usually, near-infrared lasers are used as illumination sources, ICCD devices are used to carry out laser range gating research, and the short integration time characteristics of ICCDs are used to achieve range gating.

Chinese patent CN 106506996 B describes a short-wave infrared imaging system based on linear array laser illumination and its working method. It uses linear array InGaAs detectors and linear array light sources to carry out laser gating imaging. There is no clear statement on the question, but it is mentioned that the integral delay of the integrating circuit is calculated according to the beam flight time of the laser pulse. The beam flight time can only be known when the target distance is clear.

Contents of the invention

The object of the present invention is to solve the deficiencies in the prior art, to provide a target scene distance extraction device based on an InGaAs camera, and to provide a target scene distance extraction method based on an InGaAs camera. Using high-precision time delay and image difference method, it can effectively extract the target scene while extracting the distance value of the target scene.

In order to achieve the above object, the present invention adopts the following technical measures:

The target scene distance extraction device based on InGaAs camera, including laser, timing control and image acquisition and processing module, transmitting lens, receiving lens and InGaAs camera,

The timing control and image acquisition and processing module is used to collect the digital image data output by the InGaAs camera, set the total integration time of the InGaAs camera, trigger the InGaAs camera to start integration, and control the laser to emit light;

The laser generates the laser beam required for illuminating the target scene under the trigger of the timing control and image acquisition processing module;

InGaAs camera, under the setting and triggering of the timing control and image acquisition processing module, the optical signal output by the receiving lens is collected and converted into an electrical signal, and the digital image data is output when the total integration time is over.

The launch lens projects the laser beam output by the laser to the target area,

The receiving lens receives the light signal reflected by the target scene.

A target scene distance extraction method based on an InGaAs camera, comprising the following steps:

c为光速。The timing control and image acquisition and processing module sets the total integration time of the InGaAs camera for the ith time as T _c -ΔT×(i-1), where T _c is the initial total integration time, ΔT is the number of delay steps, and then starts the laser to emit light and start Delay T ₀ +ΔT(i-1) after the laser emits light to start InGaAs camera integration. T ₀ is the initial value of the time interval. After the InGaAs camera integration is completed, digital image data is output. The timing control and image acquisition and processing module collects digital image data P _i and After completing the storage, subtract the digital image data P _i from the digital image data P _i-1 to obtain the difference data image ΔP _i-1 , and the target scene distance corresponding to the difference data image ΔP _i-1 is

c is the speed of light.

Compared with the prior art, the present invention has the following beneficial effects:

1. The minimum target scene distance has nothing to do with the minimum integration time of the InGaAs camera, but is related to the internal clock cycle of the InGaAs camera, achieving the highest precision of the InGaAs camera;

2. Through multiple imaging to form a three-dimensional image of the scene within the range of the laser beam, the target details can reach the level of passive imaging;

3. The method is applicable to any range-gated imaging system, and the method is simple and practical.

Description of drawings

Figure 1 is a composition diagram of the device of the present invention.

Fig. 2 is a schematic timing diagram of the method of the present invention.

Detailed ways

In order to facilitate those of ordinary skill in the art to understand and implement the present invention, the present invention will be described in further detail below in conjunction with the examples. It should be understood that the implementation examples described here are only used to illustrate and explain the present invention, and are not intended to limit the present invention.

As shown in Figure 1, the target scene distance extraction device based on InGaAs camera gating imaging includes a timing control and image acquisition processing module, a laser, a transmitting lens, a receiving lens and an InGaAs camera.

The timing control and image acquisition and processing module is used to collect the digital image data output by the InGaAs camera, set the working parameters and the total integration time of the InGaAs camera, trigger the InGaAs camera to start integration, and control the laser to emit light.

The laser generates the laser beam required for illuminating the target scene under the trigger of the timing control and image acquisition processing module,

InGaAs camera, under the setting and triggering of the timing control and image acquisition processing module, collects the optical signal output by the receiving lens and converts it into an electrical signal. When the total integration time is over, the digital image data is output.

The launch lens projects the laser beam output by the laser to the target area,

The receiving lens receives the light signal reflected by the target scene.

The timing control and image acquisition processing module controls the laser output laser beam and triggers the InGaAs camera integration to start according to the following timing.

The initial value of the time interval T ₀ =1us between the laser light emission moment and the InGaAs camera integration start time, the laser emits light first, the delay step number ΔT=100ns, and the initial total integration time of the InGaAs camera T _c =100us.

The timing control and image acquisition and processing module sets the total integration time of the InGaAs camera for the first time to T _c and then starts the laser to emit light. After starting the laser to emit light, delay T ₀ to start the integration of the InGaAs camera. After the integration of the InGaAs camera is completed, the digital image data is output. The timing control and _The image acquisition processing module collects digital image data P1 and completes storage;

The timing control and image acquisition and processing module sets the total integration time of the InGaAs camera to T _c -ΔT for the second time, and then starts the laser to emit light. After starting the laser to emit light, delay T ₀ +ΔT to start the integration of the InGaAs camera. After the integration of the InGaAs camera is completed, the digital image is output Data, timing control and image acquisition processing module collects digital image data _P2 and completes storage,

The timing control and image acquisition and processing module sets the total integration time of the InGaAs camera to T _c -ΔT×(i-1) for the i-th time, then starts the laser to emit light, and starts the integration of the InGaAs camera after a delay of T ₀ +ΔT(i-1). The InGaAs camera outputs digital image data after integration is completed.

c为光速。Then subtract the digital image data P ₂ from the digital image data P ₁ to obtain the differential digital image data ΔP ₁ , and the target scene distance corresponding to the differential digital image data ΔP ₁ is

c is the speed of light.

A target scene distance extraction method based on InGaAs camera gating imaging, comprising the following steps:

The timing control and image acquisition and processing module sets the total integration time of the InGaAs camera to T _c -ΔT×(i-1) for the i-th time, then starts the laser to emit light, and starts the integration of the InGaAs camera after a delay of T ₀ +ΔT(i-1). After the integration of the InGaAs camera is completed, the digital image data is output. The timing control and image acquisition processing module collects the digital image data P _i and completes the storage, and then subtracts the digital image data P _i from the digital image data P _i-1 to obtain the difference data image ΔP _i-1 , denoted as ΔP _i-1 , the target scene distance corresponding to this difference data image ΔP _i-1 is

The specific embodiments described herein are merely illustrative of the spirit of the invention. Those skilled in the art to which the present invention belongs can make various modifications or supplements to the described specific embodiments or adopt similar methods to replace them, but they will not deviate from the spirit of the present invention or go beyond the definition of the appended claims range.

Claims (1)

1. A target scene distance extraction method based on an InGaAs camera utilizes a target scene distance extraction device based on the InGaAs camera, the device comprises a laser, a time sequence control and image acquisition processing module, a transmitting lens, a receiving lens and the InGaAs camera,

the time sequence control and image acquisition processing module is used for acquiring digital image data output by the InGaAs camera, setting the total integration time of the InGaAs camera, triggering the InGaAs camera to start integration and controlling the laser to emit light;

the laser generates a laser beam required by illuminating a target scene under the triggering of the time sequence control and image acquisition processing module;

the InGaAs camera collects the optical signal output by the receiving lens under the setting and triggering of the time sequence control and image collection processing module and converts the optical signal into an electric signal, and forms digital image data output after the total integration time is finished,

an emission lens for projecting the laser beam output by the laser to a target area,

a receiving lens for receiving the light signal reflected by the target scene,

the method is characterized by comprising the following steps:

the time sequence control and image acquisition processing module sets the total integration time of the InGaAs camera to be T for the ith time_c-VT×(i-1)，T_cStarting laser to emit light, starting the laser to emit light, and delaying for T₀+ VT (i-1) Start InGaAs camera integral, T₀As the initial value of the time interval, the InGaAs camera outputs digital image data after integration is completed, and the time sequence control and image acquisition processing module acquires digital image data P_iAnd finish storing, then use the digital image data P_i-1Subtracting digital image data P_iTo obtain a difference data image VP_i-1Difference data image VP_i-1Corresponding target scene distance of

And c is the speed of light.

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