Apparatus for measuring transmittance

An apparatus (100) for measuring transmittance which can realize reliability for measurement of the transmittance of a piece of patterned glass by post dispersion of light. The apparatus (100) includes a light source (110) which is disposed in front of an object (G) that is to be measured, and directs light into the object. An integrating sphere (120) is disposed in the rear of the light source (110) and integrating light incident thereinto. The object (G) is mounted on the front portion of the integrating sphere (120). A light dispersing part (130) is disposed in the rear of the integrating sphere (120), and disperses light that has been integrated by and then emitted from the integrating sphere. An optical receiver (140) is disposed adjacent to the light dispersing part (130), and receives light that has been dispersed by the light dispersing part (130).