Adaptive quick focusing device and method for optical camera

Abstract

The invention discloses an adaptive quick focusing device for an optical camera. The adaptive quick focusing device comprises a focus detector (1), an image collector (2), a data arithmetic unit (3), a focusing drive component (9) and an encoder (7), wherein the encoder (7) is used for acquiring the position of an image surface (10) of the optical camera; the image collector (2) is used for acquiring a quantized image; the data arithmetic unit (3) is used for calculating a configuration entropy of the image; and the focus detector (1) is used for calculates configuration entropies of images at two different positions and sending focusing information to the focusing drive component (9) according to a result to drive the image surface (10) of the optical camera to reach the position of the maximum configuration entropy. An adaptive quick focusing method for the optical camera comprises the following steps of comparing the configuration entropies of images formed by the image surface (10) of the optical camera at two different positions, adjusting the moving direction according to the comparison result, and taking the position of the maximum configuration entropy of the image as the focusing position of the image surface (10) of the optical camera. The focusing speed is high, the focusing accuracy is high, and the requirement of weak contrast objects on space remote sensing is met.

Description

Technical field [0001] The invention belongs to the field of aerospace optical remote sensors, and relates to an optical camera self-adaptive fast focusing device and a corresponding method, which are used for on-track automatic focusing of the optical camera. Background technique [0002] The development of high spatial resolution optical remote sensors has always been an important part of human space technology, and high image quality is an important technical indicator of aerospace optical remote sensors. The optical camera will experience acceleration and violent vibration at the moment of launch. There is a huge pressure difference inside and outside the load compartment. Factors such as the sun and the earth’s radiation make the entire star heated unevenly. The space orbital atmospheric pressure changes with altitude. This series of temperature, Factors such as pressure and vibration will cause changes in the optical parameters such as the radius of curvature, surface shape...

AI Technical Summary

Problems solved by technology

In our country, before the satellite is launched, digital or ground physical simulation and test methods are usually used to obtain the estimated value of the best focal plane position of the optical camera during the orbit phase, and the imaging plane is preset at the focal plane, but it cannot be based on On-orbit adaptive auto-focusing in different space environments

The existing on-orbit focusing technology in China also has a method of downloading the image data to the ground. After multiple image data interpretations are performed manually, the focus control information is uploaded to realize the focus judgment and focus adjustment of the on-orbit camera. It cannot automatically adjust the focus. The focus effect depends on the richness of the imaging target details. It has high requirements on the imaging conditions and the focus speed is slow.

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