环境相关的LCTF多光谱成像控制策略

The Control Strategies of Environment-related Multi-spectral Imaging Based on LCTF

选用光学镜头、液晶可调谐滤色器和COMS工业相机,构成便携式多光谱成像仪,采集波长范围为400～720nm的多光谱图像。从实验上研究了系统的曝光时间、增益与波长的变化关系,给出了三种典型光照条件下基于液晶可调滤色器(LCTF)的多光谱成像控制策略。在同种光照条件下,对于拍摄目标场景时,曝光时间和增益随波长变化是一致的,调节时应同步(同增或同减)调节;当环境(光源)不同时,对场景的拍摄策略有明显影响;环境不同,曝光时间和增益随波长的变化有较大差异,应制定不同的拍摄策略。

The portable multi-spectral imaging system is mainly made up of expanding beam optical lens, liquid crystal tunable filter （LCTF） and monochrome COMS camera, the wavelength range of LCTF is from 400nm to 720nm. The experiment studied the relationship between exposure time and gain control with wavelength changes under the specified conditions, and obtained multispeetral imaging control strategy under three typical light conditions based on LCTF imaging. In the same light conditions, the change of exposure time and gain with the wavelength is consistent when shooting a target scene, namely, the adjustment is increasing or decreasing synchronizely; in the different light conditions, the change of exposure time and gain with the wavelength is almost diverse when shooting a target scene. Therefore, we should adapt different shooting strategies under the specified conditions.