Patent ID: 8462342

Claim:
A spectral colorimetric apparatus comprising: a concave surface reflection type diffraction element configured to disperse an incident light beam; a linear sensor including a plurality of photoelectric conversion elements each configured to receive the light beam dispersed by the concave surface reflection type diffraction element; a housing which includes a side wall and configured to support the concave surface reflection type diffraction element and the linear sensor; and an opening portion formed in the side wall of the housing arranged such that the light beam dispersed by the concave surface reflection type diffraction element passes through the opening, wherein an outer surface of the side wall is operable as an adjustment surface capable of adjusting the position of the linear sensor by moving while abutting on the linear sensor, and the linear sensor is supported by the side wall of the housing while abutting on the adjustment surface and receives the light beam that is dispersed by the concave surface reflection type diffraction element and passes through the opening portion, and wherein the adjustment surface is parallel to a tangential line at a part of a Rowland circle of the concave surface reflection type diffraction element, through which a light beam received by the linear sensor passes.