Title:
ENDOSCOPIC OPTICAL SYSTEM AND ENDOSCOPIC DEVICE
Document Type and Number:
WIPO Patent Application WO/2019/171642
Kind Code:
A1
Abstract:
The purpose of the present invention is to provide an endoscopic optical system and an endoscopic device capable of creating a suitable image by reducing astigmatism generated in a wavelength plate (depolarization plate) while achieving sufficient depolarization effects. The endoscopic optical system comprises in order from an object: an objective optical system OBL; a quarter-wave plate 121a made of a single birefringent material; a polarizing beam splitter 121 for dividing the light from the objective optical system OBL into two images; and an imaging element 122 for capturing the two divided images. The endoscopic optical system satisfies the following conditional expression (1):
1.1 ≤ Fno / (d / |∆n|) ≤ 49 (1)
Where Fno represents an effective f number in an objective optical system, d represents the thickness of the quarter-wave plate, and ∆n represents birefringence on an e-line (546.1 nm) of the quarter-wave plate, provided |0.01| <∆n.
Inventors:
TSUYUKI HIROSHI (JP)
Application Number:
PCT/JP2018/037261
Publication Date:
September 12, 2019
Filing Date:
October 04, 2018
Export Citation:
Assignee:
OLYMPUS CORP (JP)
International Classes:
G02B13/04; A61B1/00; G02B5/04; G02B5/30; G02B23/26
Domestic Patent References:
WO2017073292A1 | 2017-05-04 | |||
WO2018173412A1 | 2018-09-27 |
Foreign References:
JP2005164652A | 2005-06-23 | |||
JP2000047029A | 2000-02-18 | |||
JPH1196583A | 1999-04-09 |
Attorney, Agent or Firm:
SAITO Keisuke (JP)
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