US 12,436,329 B2
Optical device
Tsubasa Watanabe, Hamamatsu (JP); Hiroto Sakai, Hamamatsu (JP); and Yasushi Ohbayashi, Hamamatsu (JP)
Assigned to HAMAMATSU PHOTONICS K.K., Hamamatsu (JP)
Appl. No. 18/015,346
Filed by HAMAMATSU PHOTONICS K.K., Hamamatsu (JP)
PCT Filed Jun. 16, 2021, PCT No. PCT/JP2021/022915
§ 371(c)(1), (2) Date Jan. 10, 2023,
PCT Pub. No. WO2022/019010, PCT Pub. Date Jan. 27, 2022.
Claims priority of application No. 2020-124457 (JP), filed on Jul. 21, 2020.
Prior Publication US 2023/0280515 A1, Sep. 7, 2023
Int. Cl. G02B 5/28 (2006.01); G02B 1/11 (2015.01); G02B 21/00 (2006.01)
CPC G02B 5/285 (2013.01) [G02B 1/11 (2013.01); G02B 21/0092 (2013.01)] 7 Claims
OG exemplary drawing
 
1. An optical apparatus comprising:
an angle filter disposed on an optical path in the middle of focusing or divergence by a focusing optical element, wherein
the angle filter includes a dielectric multilayer film in which dielectric layers having a first refractive index and dielectric layers having a second refractive index lower than the first refractive index are alternately stacked.