公开(公告)号：US20210389178A1

公开(公告)日：2021-12-16

申请号：US17287157

申请日：2019-08-06

Applicant: HAMAMATSU PHOTONICS K.K.

Inventor： Kei TABATA ,  Masaaki MUTO

IPC: G01J3/28 ,  G01J3/02 ,  G01J3/26 ,  G02B5/28

Abstract: A spectroscopic unit includes a housing, a light incident portion provided in the housing, a Fabry-Perot interference filter arranged in the housing and having a first mirror and a second mirror, a distance between the first mirror and the second mirror being variable. The light incident portion includes an aperture portion in which an aperture is formed and a band pass filter arranged between the aperture and the Fabry-Perot interference filter. The aperture portion is configured so that a value obtained by dividing a length of the aperture in a facing direction of the first mirror and the second mirror by a width of the aperture in a direction perpendicular to the facing direction is equal to or more than 0.5 and the entirety of light passing through the aperture is incident on the band pass filter.