Development Of A Digital Interface CMOS Imaging System Based On The NSC1105 Sensor

NSC 1105 is a large sized CMOS image sensor whose size is 1 inch. As a result, it can be coupled with image intensifier by the optical fiber panel. The image sensor with image intensifier can be used as the front-end of image acquisition for low light level television and UV camera. And digital interface has been widely used in LLL TV and UV camera. As a pre-research project of LLL TV and UV camera, this paper develops a CMOS digital image system based on NSC 1105 sensor.First of all, this paper makes a presentation of the CMOS sensor's development and the Cameralink interface standard. Then according to the project requirements the system cirtuit is designed, including the power supply unit, the peripheral circuit of CMOS image sensor, AD conversion circuit, digital output interface circuit and the configuration circuit of FPGA. The placement and routing of system cirtuit is completed by PADS layout. After this, the system hardware platform is set up.Next the logic design of imaging system is developed on this hardware platform, including the driving of CMOS, image acquisition, image caching, dynamic range adjustment, image denoise and digital output modules. Two kinds of image dynamic range adjustment algorithm are used to simulate in dynamic range adjustment module. And the histogram equalization algorithm is adopted after comparing the result of simulation. Two kinds of image denoise algorithm are used to simulate in image denosie module. And the quality of the denoised image is evaluated by PSNR Evaluation which is one of the full reference image quality evaluation methods. Both algorithms are ported to the FPGA.There are two data formats to be selected in digital output module. Finally, this paper debugs the digital output interface and analyzes the image. The Cameralink interface is confirmed to be used for the transmission of image signal and communication signal. The display of 14 bit format image is analyized on microDisplay software. The 8 bit format image is analyzed when it is processed by algorithm before and after.And the histogram equalization algorithm and Gaussian filter algorithm are adopted on the imaging system.