US 11,867,930 B2
Filter module and projection apparatus
Cheng-Che Chien, Hsin-Chu (TW); Ming-Tsung Weng, Hsin-Chu (TW); and Sheng-Chiang Lin, Hsin-Chu (TW)
Assigned to Coretronic Corporation, Hsin-Chu (TW)
Filed by Coretronic Corporation, Hsin-Chu (TW)
Filed on Jul. 27, 2021, as Appl. No. 17/386,515.
Claims priority of application No. 202010748579.5 (CN), filed on Jul. 30, 2020.
Prior Publication US 2022/0035081 A1, Feb. 3, 2022
Int. Cl. G02B 5/02 (2006.01); G02B 13/16 (2006.01); G02B 5/20 (2006.01); G02B 21/14 (2006.01)
CPC G02B 5/0294 (2013.01) [G02B 5/20 (2013.01); G02B 13/16 (2013.01); G02B 21/14 (2013.01)] 15 Claims
OG exemplary drawing
 
1. A filter module, comprising a transparent substrate, a filter layer and a diffusion layer, wherein:
the transparent substrate comprises a first surface and a second surface opposite to each other, wherein light enters the transparent substrate from the first surface and leaves the transparent substrate from the second surface;
the filter layer is disposed on one of the first surface and the second surface, the filter layer comprises a first filter region and a second filter region, the first filter region and the second filter region respectively allow light having a first waveband and light having a second waveband to pass through; and
the diffusion layer is disposed on the other one of the first surface and the second surface, the diffusion layer is disposed on a side of the filter module opposite to the filter layer and comprises a first diffusion portion with a first haze value and a second diffusion portion with a second haze value, the first diffusion portion is disposed corresponding to and overlapped with the first filter region along an axial direction, and allows the corresponding light having the first waveband to pass through, and the second diffusion portion is arranged corresponding to and overlapped with the second filter region along the axial direction, and allows the corresponding light having the second waveband to pass through, and the first haze value is different from the second haze value.