# US 2020/0401235 A1 · Keyboard backlight module and applications thereof > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2020/0401235 A1 - Document ID: US20200401235A1 - Status: Published application - Kind: A1 - Application number: 16/904,276 - Filed: 2020-06-17 - Published: 2020-12-24 - Earliest claimed: 2019-06-18 - Assignees: Lite-On Electronics (Guangzhou) Limited; Lite-On Technology Corporation - Applicants: Lite-On Electronics (Guangzhou) Limited; Lite-On Technology Corporation - Inventors: Hsin-Chih LIANG - Web page: https://patentgrep.com/patent/US20200401235A1 ## CPC - G02B 6/0021: {for housing at least a part of the light source, e.g. by forming holes or recesses} - G02B 6/0031: {Reflecting element, sheet or layer} - G02B 6/0036: {2-D arrangement of prisms, protrusions, indentations or roughened surfaces} - G02B 6/0055: {Reflecting element, sheet or layer} - G06F 3/0202: {Constructional details or processes of manufacture of the input device} - H01H 3/125: {using a scissor mechanism as stabiliser} - H01H 13/14: Operating parts, e.g. push-button - H01H 13/704: characterised by the layers, e.g. by their material or structure (H01H13/703 takes precedence) - H01H 13/705: characterised by construction, mounting or arrangement of operating parts, e.g. push-buttons or keys - H01H 13/7057: characterised by the arrangement of operating parts in relation to each other, e.g. pre-assembled groups of keys - H01H 13/785: characterised by the material of the contacts, e.g. conductive polymers - H01H 13/83: characterised by legends, e.g. Braille, liquid crystal displays, light emitting or optical elements - G02B 6/0073: {Light emitting diode [LED]} - G02B 6/0088: {of the light guide or other optical sheets in the package} - G02B 6/009: {of the light source in the package (G02B6/0021 takes precedence)} - G02B 6/0091: {of the light source relative to the light guide (G02B6/0021 takes precedence)} - H01H 2203/052: for backlighted keyboards - H01H 2219/039: Selective or different modes of illumination - H01H 2219/056: Diffuser; Uneven surface - H01H 2219/06: Reflector - H01H 2219/062: Light conductor - H01H 2221/058: to avoid tilting or skewing of contact area or actuator - H01H 2221/066: replaceable - H01H 2229/044: Injection moulding - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) - H01H: ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES (contact cables H01B7/10; electrolytic self-interrupters H01G9/18; emergency protective circuit arrangements H02H; switching by electronic means without contact-making H03K17/00) ## Abstract A keyboard backlight module includes a light guide plate, a reflector, a light-emitting device and a first microstructure. The light guide plate has an output surface, a light guide pattern and a bottom surface disposed on an opposite side of the output surface. The light guide pattern is arranged on at least one of the bottom surface and the output surface. The reflector has a reflecting surface facing the bottom surface. The light-emitting device is disposed on one side of the light guide plate and configured to provide an incident light to the reflecting surface. The first microstructure is disposed on the reflecting surface, at least partially overlaps with the light guide pattern, and is configured to transform the incident light into a first reflected light. ## Claims ### Claim 1 A keyboard backlight module, comprising: a light guide plate, having an output surface, a light guide pattern and a bottom surface, wherein the bottom surface is disposed on an opposite side of the output surface, and the light guide pattern is arranged on at least one of the bottom surface and the output surface; a reflector, having a reflecting surface facing the bottom surface; a light-emitting device, disposed on one side of the light guide plate and configured to provide an incident light to the reflecting surface; and a first microstructure, disposed on the reflecting surface, and at least partially overlapping with the light guide pattern, wherein a first reflected light is formed by a portion of the incident light via the first microstructure. ### Claim 2 (depends on 1) The keyboard backlight module according to claim 1, wherein the reflecting surface has a first region and a second region, a distance between the first region and the light-emitting element is smaller than a distance between the second region and the light-emitting element; and a portion of the first microstructure disposed in the first region has a configuration different from that of another portion of the first microstructure disposed in the second region. ### Claim 3 (depends on 1) The keyboard backlight module according to claim 1, wherein the first microstructure is a light-absorbing feature, the reflecting surface has a first region and a second region with substantially equal areas, the first region is closer to the light-emitting device than the second region, and a first area occupied by a portion of the first microstructure disposed in the first region is larger than a second area occupied by another portion of the first microstructure disposed in the second region. ### Claim 4 (depends on 1) The keyboard backlight module according to claim 1, wherein the first microstructure has at least one first reflective surface facing the light-emitting device; and the at least one first reflective surface and the reflecting surface form a first angle less than or equal to 90°. ### Claim 5 (depends on 4) The keyboard backlight module according to claim 4, wherein the reflecting surface has a first region and a second region with substantially equal areas, the first region is closer to the light-emitting device than the second region, a first number of the first reflective surfaces are disposed in the first region, a second number of the first reflecting surfaces are disposed in the second region, and the first number is smaller than the second number. ### Claim 6 (depends on 5) The keyboard backlight module according to claim 5, wherein the light guide pattern has a first number of at least one light-guiding dot corresponding to the first region and a second number of at least one light-guiding dot corresponding to the second region, and the first number is smaller than the second number. ### Claim 7 (depends on 4) The keyboard backlight module according to claim 4, further comprising a second microstructure configured to transform another portion of the incident light into a second reflected light, wherein the reflecting surface has a first region and a second region with substantially equal areas; the first region is closer to the light-emitting device than the second region; the first microstructure is disposed in the first region and the second microstructure is disposed in the second region; the second microstructure has at least one second reflective surface facing the light-emitting device, and the at least one second reflective surface and the reflecting surface form a second angle smaller than the first angle. ### Claim 8 (depends on 7) The keyboard backlight module according to claim 7, wherein the light guide pattern has a first number of at least one light-guiding dot corresponding to the first region and a second number of at least one light-guiding dot corresponding to the second region, and the first number is smaller than the second number. ### Claim 9 (depends on 1) The keyboard backlight module according to claim 1, further comprising a second microstructure configured to transform another portion of the incident light into a second reflected light, wherein the reflecting surface has a first region and a second region with substantially equal areas; the first region is closer to the light-emitting device than the second region; the first microstructure is disposed in the first region and has a first light-shielding area; and the second microstructure is disposed in the second region and has a second light-shielding area smaller than the first light-shielding area. ### Claim 10 (depends on 9) The keyboard backlight module according to claim 9, wherein the light guide pattern has a first number of at least one light-guiding dot corresponding to the first region and a second number of at least one light-guiding dot corresponding to the second region, and the first number is smaller than the second number. ### Claim 11 (depends on 1) The keyboard backlight module according to claim 1, wherein the first microstructure includes at least one protruding portion convexly protruding outwards from the reflecting surface, or at least one concave portion concavely recessed inwards to the reflector from the reflecting surface. ### Claim 12 (depends on 11) The keyboard backlight module according to claim 11, further comprising at least one light-absorbing material at least partially overlapping the at least one protruding portion or the at least one concave portion. ### Claim 13 (depends on 1) The keyboard backlight module according to claim 1, wherein the light guide pattern has at least one light-guiding dot; and a single unit of the first microstructure has an area larger than an area of a single unit of the at least one light-guiding dot. ### Claim 14 A backlit keyboard, comprising: a keyboard backlight module, comprising: a light guide plate, having an output surface, a light guide pattern and a bottom surface, wherein the bottom surface is disposed on an opposite side of the output surface, and the light guide pattern is arranged on at least one of the bottom surface and the output surface; a reflector, having a reflecting surface facing the bottom surface; a light-emitting device, disposed on one side of the light guide plate; and a first microstructure, disposed on the reflecting surface, and at least partially overlapping with the light guide pattern; and a key switch module, comprising at least one key switch and disposed on one side of the keyboard backlight module. ### Claim 15 (depends on 14) The backlit keyboard according to claim 14, wherein a portion of the light guide pattern and a portion of the first microstructure are correspondingly arranged below the at least one key switch. ### Claim 16 (depends on 14) The backlit keyboard according to claim 14, wherein the reflecting surface has a first region and a second region, a distance between the first region and the light-emitting element is smaller than a distance between the second region and the light-emitting element; and a portion of the first microstructure disposed in the first region has a configuration different from that of another portion of the first microstructure disposed in the second region. ### Claim 17 (depends on 14) The backlit keyboard according to claim 14, wherein the first microstructure is a light-absorbing feature, the reflecting surface has a first region and a second region with substantially equal areas, the first region is closer to the light-emitting device than the second region, and a first area occupied by a portion of the first microstructure disposed in the first region is larger than a second area occupied by another portion of the first microstructure disposed in the second region. ### Claim 18 (depends on 14) The backlit keyboard according to claim 14, wherein the first microstructure has at least one first reflective surface facing the light-emitting device; and the at least one first reflective surface and the reflecting surface form a first angle less than or equal to 90°. ### Claim 19 (depends on 18) The backlit keyboard according to claim 18, wherein the reflecting surface has a first region and a second region with substantially equal areas, the first region is closer to the light-emitting device than the second region, a first number of the first reflective surfaces are disposed in the first region, a second number of the first reflecting surfaces are disposed in the second region, and the first number is smaller than the second number. ### Claim 20 (depends on 14) The backlit keyboard according to claim 14, further comprising a second microstructure, wherein the reflecting surface has a first region and a second region with substantially equal areas; the first region is closer to the light-emitting device than the second region; the first microstructure is disposed in the first region and has a first light-shielding area; and the second microstructure is disposed in the second region and has a second light-shielding area smaller than the first light-shielding area.