| abstract |
A portable digital image capturing and processing system comprising: an image formation and detection subsystem; a narrow-band illumination subsystem; a narrow-band transmission-type optical filter subsystem; an automatic light exposure measurement subsystem; and an automatic illumination control subsystem. The image formation and detection subsystem has an area-type image sensing array for detecting digital images of objects formed thereon by image formation optics providing a field of view (FOV) for the system. Within the FOV of the image formation and detection subsystem, the narrow-band illumination subsystem produces a field of narrow-band illumination consisting essentially of a narrow band of wavelengths of visible illumination. The narrow-band transmission-type optical filter subsystem transmits substantially only the narrow band of wavelengths of visible illumination produced from the narrow-band illumination subsystem, and rejects all other optical wavelengths outside the narrow band however generated by ambient illumination sources. The automatic light exposure measurement subsystem employs a photo-detector operated independently from the area-type image sensing array, for automatically measuring the light exposure incident upon a selected portion of the FOV, and producing an electrical signal representative of the light exposure measurement. The automatic illumination control subsystem responds to the electrical signal and controls the duration of narrow-band illumination produced from the narrow-band illumination subsystem. |