| 摘要 |
For a portable image capture application involving a need for very reliable simultaneous capture of a plurality of images of coded labels (106) each upon a varying object and under uncontrolled ambient lighting, the invention provides an electronic camera (111) and lighting elements (101) adapted to overpower the contribution of any ambient light on the captured image. Thus highlights and shadows inside recesses are similarly lit. The main device (100) is using a brief (< 100 uS, typically about 60 uS) flash of powerful light and a ferromagnetic liquid crystal shutter open only within the period of the flash. Matching spectral bands of flashed and admitted light contributes to the objective; so does linear polarizing/analyzing to reject specular reflections. The spectral limits between deep orange and infrared (at about 1 micron) also minimize the risk of startling nearby personnel, although other bands could be used. |
