Modulation transfer function test method of multichannel CCD

Abstract

The invention relates to a CCD test technology and discloses a modulation transfer function test method of a multichannel CCD. The modulation transfer function test method of the multichannel CCD solves the problem that an existing multichannel CCD is not accurate in test result as responses of channels are not consistent. A high-stability light source is adopted, and output of the light source is adjusted to enable the grey value of a reference white board to be 80% of the maximum output DN grey value when the gain and bias are zero; that four pixel grey values of adjacent channels in the reference white board of a target are the closest serves as the standard, and the bias and gain parameters of the channels are adjusted; the best modulation transfer function is searched for through micro movement of a rotary table, and the pixel range of an effective test result of the modulation transfer function is limited strictly according to the position of the target; the rotary table is adopted to move a camera, the target image moves by one pixel position, and the maximum modulation transfer function and the maximum deviation value are counted through the image obtained before and after the image is moved. The modulation transfer function test method of the multichannel CCD reduces difficulty of matching of the target image and the CCD and influence on the test result of the modulation transfer function from fluctuation of a power source.

Description

technical field

[0001] The invention relates to a CCD test technology, in particular to a test method for multi-channel CCD modulation transfer function. Background technique

[0002] The modulation transfer function is an important indicator of a CCD camera, and it is also an important basis for testing the imaging quality of the camera at each stage of optical design and assembly. A test method of CCD modulation transfer function is a contrast test based on a rectangular target. During the test process, the test results are affected by the vibration of the external environment, the signal-to-noise ratio, the stability of the lighting source, the modulation degree of the target itself, the registration degree of the target image and the CCD pixel, the inhomogeneity of the CCD pixel and the channel inconsistency The impact will lead to inaccurate test results and even large deviations.

[0003] When the CCD camera is imaging, the processes of light, mechanics, electricity,...

Examples

specific Embodiment approach 1

[0018] Specific implementation mode 1. Combination Figure 1 to Figure 4 Illustrate this embodiment, the modulation transfer function test method of multi-channel CCD, this method is realized by the following steps:

[0019] 1. The power supply ripple of the integrating sphere is not higher than 10mV. The target adopts a part of the glass structure with full light transmission, and a part of the grating structure with light transmission and total reflection through coating; the gain and bias parameters of the camera are required to be 0 When adjusting the integrating sphere, the image gray value of the fully transparent white board structure of the target is 80% ± 1% of the maximum output gray value of the camera;

[0020] 2. For the adjustment of the consistency of the multi-channel CCD channels, the images of the target whiteboard structure are in different channels by rotating the turntable, and the four pixel gray values ​​of the adjacent channels are closest to each other...

technical field

[0001] The invention relates to a CCD test technology, in particular to a test method for multi-channel CCD modulation transfer function. Background technique

[0002] The modulation transfer function is an important indicator of a CCD camera, and it is also an important basis for testing the imaging quality of the camera at each stage of optical design and assembly. A test method of CCD modulation transfer function is a contrast test based on a rectangular target. During the test process, the test results are affected by the vibration of the external environment, the signal-to-noise ratio, the stability of the lighting source, the modulation degree of the target itself, the registration degree of the target image and the CCD pixel, the inhomogeneity of the CCD pixel and the channel inconsistency The impact will lead to inaccurate test results and even large deviations.

[0003] When the CCD camera is imaging, the processes of light, mechanics, electricity,...

Examples

specific Embodiment approach 1

[0018] Specific implementation mode 1. Combination Figure 1 to Figure 4 Illustrate this embodiment, the modulation transfer function test method of multi-channel CCD, this method is realized by the following steps:

[0019] 1. The power supply ripple of the integrating sphere is not higher than 10mV. The target adopts a part of the glass structure with full light transmission, and a part of the grating structure with light transmission and total reflection through coating; the gain and bias parameters of the camera are required to be 0 When adjusting the integrating sphere, the image gray value of the fully transparent white board structure of the target is 80% ± 1% of the maximum output gray value of the camera;

[0020] 2. For the adjustment of the consistency of the multi-channel CCD channels, the images of the target whiteboard structure are in different channels by rotating the turntable, and the four pixel gray values ​​of the adjacent channels are closest to each other...

Images