# US 10,884,181 B2 · Backlight and display apparatus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,884,181 B2 - Document ID: US10884181B2 - Status: Granted - Kind: B2 - Application number: 16/728,228 - Filed: 2019-12-27 - Published: 2020-07-23 - Granted: 2021-01-05 - Earliest claimed: 2019-01-23 - Assignees: Mitsubishi Electric Corporation - Applicants: Mitsubishi Electric Corporation - Inventors: Hiroshi Teramoto - Web page: https://patentgrep.com/patent/US10884181B2 ## CPC - G02B 6/0088: {of the light guide or other optical sheets in the package} - G02B 6/0091: {of the light source relative to the light guide (G02B6/0021 takes precedence)} - G02B 6/0021: {for housing at least a part of the light source, e.g. by forming holes or recesses} - G02B 6/0073: {Light emitting diode [LED]} - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS ## Abstract The rear frame includes a frame-like body and a protrusion. The protrusion projects from an inner surface of the frame-like body. A light source unit is disposed on the inner surface, and includes a point light source. The light incident surface on a side surface of the light guide plate faces a light-emitting surface with a gap. An abutting side surface of the light guide plate projects toward the inner surface. The protrusion is fitted to a recess on the abutting side surface. The joining medium joins the abutting side surface with the light source unit. Alternatively, a projecting portion of the light guide plate projects in a direction different from a direction in which the abutting side surface projects. The intermediate frame sandwiches the light guide plate together with the rear frame and includes a sandwiching portion. The sandwiching portion sandwiches the projecting portion. ## Claims ### Claim 1 A backlight, comprising: a rear frame including a frame-like body having an inner surface, and a protrusion projecting from the inner surface; a light source unit that is housed in the rear frame, is disposed on the inner surface, and includes a point light source having a light-emitting surface; a light guide plate that is housed in the rear frame, has a side surface having a light incident surface facing the light-emitting surface with a gap between the light incident surface and the light-emitting surface, and an abutting side surface that projects toward the inner surface more than the light incident surface, and has a recess to which the protrusion is fitted on the abutting side surface; and an adhesive joining medium that holds together the abutting side surface with the light source unit. ### Claim 2 (depends on 1) The backlight according to claim 1, wherein the rear frame includes a side wall having the inner surface, and the protrusion has a height 0.5 times or more and 1.0 times or less a thickness of the side wall. ### Claim 3 (depends on 1) The backlight according to claim 1, wherein the light source unit has a hole, and the protrusion penetrates the hole. ### Claim 4 (depends on 1) The backlight according to claim 1, wherein the light-emitting surface is parallel to the light incident surface. ### Claim 5 (depends on 1) The backlight according to claim 1, wherein the rear frame includes a plurality of protrusions projecting from the inner surface, the side surface has a plurality of abutting side surfaces, the light guide plate respectively has a plurality of recesses on the plurality of abutting side surfaces, and the plurality of protrusions are respectively fitted to the plurality of recesses. ### Claim 6 (depends on 1) A display apparatus, comprising: the backlight according to claim 1; and a display panel illuminated by the backlight. ### Claim 7 A backlight, comprising: a rear frame including a frame-like body having an inner surface, and a protrusion projecting from the inner surface; a light source unit that is housed in the rear frame, is disposed on the inner surface, and includes a point light source having a light-emitting surface; a light guide plate that is housed in the rear frame, has a main surface that is opposite to the rear frame and configured to emit light, has a side surface having a light incident surface facing the light-emitting surface with a gap between the light incident surface and the light-emitting surface, and an abutting side surface that projects toward the inner surface more than the light incident surface, has a recess to which the protrusion is fitted on the abutting side surface, and a projecting portion projecting in a direction different from a direction in which the abutting side surface projects; and an intermediate frame that sandwiches the light guide plate together with the rear frame in a direction perpendicular to the main surface of the light guide plate, and includes a sandwiching portion that sandwiches the projecting portion from a direction perpendicular to the inner surface and parallel to the main surface of the light guide plate. ### Claim 8 (depends on 7) The backlight according to claim 7, wherein the rear frame includes a side wall having the inner surface, and the protrusion has a height 0.5 times or more and 1.0 times or less a thickness of the side wall. ### Claim 9 (depends on 7) The backlight according to claim 7, wherein the light source unit has a hole, and the protrusion penetrates the hole. ### Claim 10 (depends on 7) The backlight according to claim 7, wherein the light-emitting surface is parallel to the light incident surface. ### Claim 11 (depends on 7) The backlight according to claim 7, wherein the rear frame includes a plurality of protrusions projecting from the inner surface, the side surface has a plurality of abutting side surfaces, the light guide plate respectively has a plurality of recesses on the plurality of abutting side surfaces, and the plurality of protrusions are respectively fitted to the plurality of recesses. ### Claim 12 (depends on 7) A display apparatus, comprising: the backlight according to claim 7; and a display panel illuminated by the backlight. ### Claim 13 (depends on 1) The backlight according to claim 1, wherein the protrusion is disposed at the inner surface. ### Claim 14 (depends on 7) The backlight according to claim 7, wherein the protrusion is disposed at the inner surface.