CN-121357418-B - Focusing method and system of infrared camera

CN121357418BCN 121357418 BCN121357418 BCN 121357418BCN-121357418-B

Abstract

A focusing method and a focusing system for an infrared camera relate to the field of motor control and solve the problems of high labor cost, easy misshooting, low efficiency and easy failure of focusing existing in the existing infrared focusing method technology. A focusing method of infrared camera includes moving infrared lens to forward maximum defocusing position when target shooting position is received, carrying out peak searching by taking coarse focal depth distance as step length to obtain maximum definition value and secondary definition value and corresponding encoder position, moving infrared lens from maximum definition value to secondary definition value by taking fine focal depth distance as step length to find maximum definition value again, and moving infrared lens to encoder position corresponding to maximum definition value to finish focusing. A focusing system of an infrared camera comprises an infrared detector, a system control module, a motor driver and an encoder. The invention is suitable for the field of automatic focusing of infrared cameras.

Inventors

DING ZHAOYU

Assignees

长春通视光电技术股份有限公司

Dates

Publication Date: 20260512
Application Date: 20251219

Claims (4)

1. A focusing method of an infrared camera, comprising the steps of: step S01, when a target shooting position is received, a driving signal is sent to move the infrared lens to a forward maximum defocusing position; Step S02, taking the coarse focal depth distance as a step length, sending a driving signal to control the infrared lens to move towards the reverse maximum defocus position, and performing the following operation when the infrared lens moves by one step: transmitting a one-time triggering exposure signal and collecting pictures, and collecting the position of an encoder fed back by the encoder to obtain a group of data, wherein the group of data comprises the position of the encoder and the pictures; Based on all the pictures obtained at present, carrying out peak searching according to the definition values of the pictures to obtain a maximum definition value and a secondary definition value, and obtaining the corresponding encoder positions; step S03, transmitting a driving signal to control the infrared lens to move to the encoder position corresponding to the maximum definition value, Taking the fine focal depth distance as a step length, sending a driving signal, controlling the infrared lens to move to the encoder position corresponding to the sub-definition value for a plurality of times, sending a trigger exposure signal once and collecting pictures once every time of movement, and collecting the encoder position to obtain a plurality of groups of data, wherein each group of data comprises pictures and the encoder position; step S04, sorting all the pictures obtained in the step S03 from large to small according to the definition values of the pictures to obtain the maximum definition values; The coarse depth of focus distance in step S02 is 1 to 5 depth of focus distances; The fine focal depth distance in the step S03 is 1/8 to 1/2 of the coarse focal depth distance; The multiple times in the step S03 are 5 to 10 times; the peak searching in step S02 is as follows: If the maximum definition value and the next two continuous definition values in all the obtained pictures form a decreasing relation, and the second definition value is smaller than half of the maximum definition value, taking the maximum definition value as the maximum definition value, taking the first definition value as the next definition value, and ending peak searching; When the infrared lens moves to the reverse maximum defocus position, the peak searching is not finished, all the obtained pictures are ordered from big to small, wherein the third clear value is smaller than 0.5 of the first clear value, the first clear value is used as the maximum clear value, the second clear value is used as the secondary clear value, and the peak searching is finished; And the focal depth distance is obtained by carrying out actual test on the infrared camera, and the displacement of the infrared lens movement corresponding to 1 focal depth is taken as the focal depth distance.
2. A focusing system of an infrared camera, wherein the focusing method is the focusing method as claimed in claim 1, and the focusing system comprises an infrared detector, a system control module, a motor driver and an encoder; the encoder is used for sending the encoder position to the system control module; The system control module is used for sending a trigger exposure signal to the infrared detector according to a focusing method and sending a driving signal to the motor driver; the infrared detector is used for collecting pictures and sending the obtained pictures to the system control module; and the motor driver is used for controlling the infrared lens to move.
3. The focusing system of claim 2, further comprising a left limit sensor and a right limit sensor; The left limit sensor is used for sending a left limit signal to the system control module when the infrared lens moves to the forward maximum defocus position; the right limit sensor is used for sending a right limit signal to the system control module when the infrared lens moves to the reverse maximum defocus position.
4. The focusing system of claim 2, further comprising an infrared camera focusing motor, a cam, a guide pin, and a focusing group; The motor driver is used for controlling the rotating speed and the steering of the infrared camera focusing motor according to the driving signal; the infrared camera focusing motor is used for driving the cam to rotate; The cam is used for driving the focusing group to move through the guide pin and driving the infrared lens to move.

Description

Focusing method and system of infrared camera Technical Field The invention relates to the field of motor control, in particular to the field of infrared cameras. Background In the camera control process, automatic focusing is an indispensable function, and the clear position of the camera lens design can be influenced by humidity, air pressure, relative mechanical angles of imaging targets and other external influences to generate a defocusing phenomenon, so that after image distortion, the corresponding position of the lens needs to be corrected by utilizing a motor-driven focusing mechanism, and the picture is clear to recover. The manual focusing function can correct the defocusing amount generated by factors such as environment, but is not intelligent enough, manual participation is needed, namely, the defocusing range is manually traversed step by step, meanwhile, the clear condition of the picture is identified through human eyes, the utilization rate of equipment is reduced, and the corresponding labor cost in the use process of a camera is increased. The traditional infrared automatic focusing method mainly utilizes the corresponding relation between the returned clear value of the camera and the value of the lens encoder to search peaks and search, and determines the position value corresponding to the clear value. In summary, the existing infrared focusing method has the problems of high labor cost, easy misshooting, low efficiency and easy focusing failure. Disclosure of Invention The invention relieves the problems of high labor cost, easy misshooting, low efficiency and easy failure of focusing existing in the existing infrared focusing method technology. The invention provides the following scheme: the first scheme is a focusing method of an infrared camera, comprising the following steps: step S01, when a target shooting position is received, a driving signal is sent to move the infrared lens to a forward maximum defocusing position; Step S02, taking the coarse focal depth distance as a step length, sending a driving signal to control the infrared lens to move towards the reverse maximum defocus position, and performing the following operation when the infrared lens moves by one step: transmitting a one-time triggering exposure signal and collecting pictures, and collecting the position of an encoder fed back by the encoder to obtain a group of data, wherein the group of data comprises the position of the encoder and the pictures; Based on all the pictures obtained at present, carrying out peak searching according to the definition values of the pictures to obtain a maximum definition value and a secondary definition value, and obtaining the corresponding encoder positions; step S03, transmitting a driving signal to control the infrared lens to move to the encoder position corresponding to the maximum definition value, Taking the fine focal depth distance as a step length, sending a driving signal, controlling the infrared lens to move to the encoder position corresponding to the sub-definition value for a plurality of times, sending a trigger exposure signal once and collecting pictures once every time of movement, and collecting the encoder position to obtain a plurality of groups of data, wherein each group of data comprises pictures and the encoder position; And step S04, sorting all the pictures obtained in the step S03 from large to small according to the definition values of the pictures to obtain the maximum definition value, and sending a driving signal to control the infrared lens to move to the encoder position corresponding to the maximum definition value so as to finish focusing. Further, in one embodiment of the present invention, the coarse depth of focus distance in step S02 is 1 to 5 depth of focus distances. Further, in an embodiment of the present invention, the fine focal depth distance in step S03 is 1/8 to 1/2 of the coarse focal depth distance. Further, in one embodiment of the present invention, the number of times in step S03 is 5 to 10. Further, in one embodiment of the present invention, the peak-finding search in step S02 is: If the maximum definition value and the next two continuous definition values in all the obtained pictures form a decreasing relation, and the second definition value is smaller than half of the maximum definition value, taking the maximum definition value as the maximum definition value, taking the first definition value as the next definition value, and ending peak searching; And when the infrared lens moves to the reverse maximum defocus position, the peak searching is not finished, sorting all obtained pictures from big to small, wherein the third clear value is smaller than 0.5 of the first clear value, the first clear value is used as the maximum clear value, the second clear value is used as the secondary clear value, and the peak searching is finished. The second scheme is a focusing system of the infrared camera, and the focusing met