US 12,259,615 B2
Backlight apparatus and liquid crystal display apparatus
Satsuki Hagihara, Kameyama (JP); Kazuhiko Negoro, Kameyama (JP); Mayumi Hori, Kameyama (JP); and Kenichi Iwamoto, Kameyama (JP)
Assigned to Sharp Display Technology Corporation, Kameyama (JP)
Filed by Sharp Display Technology Corporation, Kameyama (JP)
Filed on May 8, 2024, as Appl. No. 18/658,856.
Claims priority of provisional application 63/471,947, filed on Jun. 8, 2023.
Prior Publication US 2024/0411178 A1, Dec. 12, 2024
Int. Cl. G02F 1/1335 (2006.01); G02F 1/13357 (2006.01)
CPC G02F 1/133614 (2021.01) [G02F 1/133603 (2013.01); G02F 1/133605 (2013.01); G02F 1/133607 (2021.01)] 12 Claims
OG exemplary drawing
 
1. A backlight apparatus comprising:
a light-emitting diode (LED) substrate having a principal surface over which a plurality of light-emitting elements that emits excitation light is arrayed;
a phosphor layer containing a phosphor that emits fluorescence upon receiving the excitation light;
a wavelength-selective reflecting layer disposed between the phosphor layer and the LED substrate, the wavelength-selective reflecting layer having different transmittances according to wavelengths and/or angles of incidence of light falling thereon; and
a louver film disposed between the wavelength-selective reflecting layer and the LED substrate and having a plurality of louvers, the louver film blocking the fluorescence and the excitation light falling thereon at an angle greater than or equal to a first angle and smaller than 90 degrees with respect to a direction normal to a film surface of the louver film, wherein
the louver film is supported by the LED substrate, and
each of the plurality of louvers is disposed in such a position as not to overlap each of the plurality of light-emitting elements when seen in a direction normal to the principal surface of the LED substrate.