MULTIELEMENT IMAGE PICKUP DEVICE

PURPOSE: To prevent deterioration of image forming characteristic (resolution) at the boundary part of an reflection area and a transmission area by gradually varying the reflectance of the boundary part of the reflection area and the transmission area in terms of a position and make reflectance incline lest spot light only reflects at one part and only transmits at another part. CONSTITUTION: At the boundary part of a spectroscope unit, the thickness of a reflection film 13 composing the reflection area is gradually made thinner toward the transmission area and the reflectance at the reflection film 13 is reduced as the reflection position comes near the transmission area. Thereby, the output of a detector on a reflection side and a transmission side which overlap at the boundary part is reduced or increased gradually. In this case, concerning spot light passing through the part of a spectroscope unit, a part of spot is no longer cut completely by the spectroscope unit to prevent the deterioration of the image forming characteristic (resolution) owing to diffraction, which is generated in a conventional system. In addition, the multielement of the image pickup device is embodied by this.