| 摘要 |
PROBLEM TO BE SOLVED: To solve a problem that in a monitor camera, a housing with an optical window to be protected or invisible from outside is mounted thereon and there is a case where the optical window is comprised of a lowered transmittance smoked color so as to be removable or invisible from outside depending on use environment but if spectral transmittance of the optical window is not properly determined, color balance of an image picked up by the monitor camera is lost when removably mounting the optical window on the housing. SOLUTION: Spectral transmittance of an optical window is adjusted so that a change between transmissive light quantitative ratio of red and green determined when mounting the optical window in front of the optical system and the transmissive light quantitative ratio of blue and green is maintained within≤5.0% on the basis of the transmissive light quantitative ratio of red and green and the transmissive light quantitative ratio of blue and green obtained by integrating from a visible wavelength region to an infrared wave length region based on composite transmittance of an image pick-up optical system, an infrared cut filter and image sensor color filter. COPYRIGHT: (C)2010,JPO&INPIT |
