US 12,000,734 B2
Optical system for spectrometers
Heinz Jürgen Graf, Kalkar (DE); and Rainer Simons, Kranenburg (DE)
Assigned to HITACHI HIGH-TECH ANALYTICAL SCIENCE GMBH, Uedem (DE)
Appl. No. 17/774,851
Filed by HITACHI HIGH-TECH ANALYTICAL SCIENCE GMBH, Uedem (DE)
PCT Filed Nov. 6, 2020, PCT No. PCT/EP2020/081343
§ 371(c)(1), (2) Date May 5, 2022,
PCT Pub. No. WO2021/089817, PCT Pub. Date May 14, 2021.
Claims priority of application No. 19207778 (EP), filed on Nov. 7, 2019.
Prior Publication US 2022/0397455 A1, Dec. 15, 2022
Int. Cl. G01J 3/02 (2006.01); G01J 3/20 (2006.01)
CPC G01J 3/0208 (2013.01) [G01J 3/021 (2013.01); G01J 3/20 (2013.01)] 12 Claims
OG exemplary drawing
 
1. An optical system comprising:
at least one entrance aperture for entering light to be analyzed,
at least one diffraction grating for spectral dispersion of the light,
at least two detectors to measure a spectrum of the light, where the detectors are arranged on a same side of a plane of dispersion of the optical system, and
at least two vertically focusing mirror elements for focusing the light onto said detectors assigned to said vertically focusing mirror elements, characterized in that
the vertically focusing mirror elements are arranged as front row mirror elements and back row mirror elements along two polygon graphs offset to each other and to a focal curve, where each section of the polygon graph is parallel to its dedicated local tangent to the focal curve of the grating, such that
angles of deflection for the front row mirror elements are <90° allowing to minimize the offset of the front row mirror elements to the focal curve,
distances between said front row mirror elements and corresponding detectors assigned to said front row mirror elements is minimized while still avoiding collisions between the corresponding detectors and their mounts with back row detectors and their mounts, and
at least one end of said front row mirror element is overlapping adjacent back row mirror element or a receptive area of an adjacent direct light detector if regarded from the grating.