# US 10,481,465 B2 · Illumination device and display device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,481,465 B2 - Document ID: US10481465B2 - Status: Granted - Kind: B2 - Application number: 15/923,049 - Filed: 2018-03-16 - Published: 2018-09-27 - Granted: 2019-11-19 - Earliest claimed: 2017-03-23 - Assignees: Japan Display Inc. - Applicants: Japan Display Inc. - Inventors: Takayuki Nakanishi; Tatsuya Yata; Takeo Koito - Web page: https://patentgrep.com/patent/US10481465B2 ## CPC - G02F 1/29: for the control of the position or the direction of light beams, i.e. deflection - G02F 1/134309: {characterised by their geometrical arrangement} - G02F 1/134363: {for applying an electric field parallel to the substrate, i.e. in-plane switching [IPS]} - G02F 1/1347: Arrangement of liquid crystal layers or cells in which the final condition of one light beam is achieved by the addition of the effects of two or more layers or cells - G02F 1/13471: {in which all the liquid crystal cells or layers remain transparent, e.g. FLC, ECB, DAP, HAN, TN, STN, SBE-LC cells (G02F1/13475 takes precedence)} - G02F 1/13362: {providing polarized light, e.g. by converting a polarisation component into another one} - G02F 1/294: {Variable focal length devices} - G02F: OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS ## Abstract According to one embodiment, an illumination device includes a light source unit which emits light, a modulation element includes a modulation portion which modulates incident light, and a non-modulation portion which is adjacent to the modulation portion, and a liquid crystal element located between the light source unit and the modulation element, the liquid crystal element forming a lens between the light source unit and the modulation portion. ## Claims ### Claim 1 An illumination device comprising: a light source unit which emits light; a modulation element comprising a modulation portion which modulates incident light, and a non-modulation portion which is adjacent to the modulation portion; and a liquid crystal element located between the light source unit and the modulation element, the liquid crystal element forming a lens between the light source unit and the modulation portion, wherein the modulation portion is smaller than the non-modulation portion, the modulation element comprises a third substrate comprising a plurality of third control electrodes, a fourth substrate comprising a fourth control electrode, and a second liquid crystal layer held between the third substrate and the fourth substrate, the second liquid crystal layer includes liquid crystal molecules twisted-aligned in a state where no electric field is formed between the third control electrodes and the fourth control electrode, the liquid crystal molecules in the non-modulation portion are vertically aligned by the electric field, the liquid crystal molecules in the modulation portion are twisted-aligned, and the modulation portion is arranged at a position where light is converged by the lens. ### Claim 2 (depends on 1) The illumination device of claim 1, further comprising a controller which controls the liquid crystal element, wherein the liquid crystal element comprises a first substrate comprising a plurality of first control electrodes, a second substrate comprising a second control electrode, and a first liquid crystal layer held between the first substrate and the second substrate, and the controller controls a voltage to be applied to the first liquid crystal layer for forming the lens which is opposed to the modulation portion in the first liquid crystal layer. ### Claim 3 (depends on 2) The illumination device of claim 2, wherein: each of the first control electrodes is a strip electrode; and the modulation portion is located between two first control electrodes. ### Claim 4 (depends on 1) The illumination device of claim 1, further comprising a controller which controls the modulation element, wherein the controller controls a voltage to be applied to the second liquid crystal layer for forming the modulation portion and the non-modulation portion in the second liquid crystal layer. ### Claim 5 (depends on 1) The illumination device of claim 1, wherein: a polarizer is nonexistent between the light source unit and the liquid crystal element; and a polarizer is nonexistent between the liquid crystal element and the modulation element. ### Claim 6 (depends on 5) The illumination device of claim 5, wherein: emitted light which is emitted from the light source unit, and transmitted light which is transmitted through the modulation element, include first polarized light and second polarized light, respectively; a ratio of the first polarized light in the transmitted light is smaller than a ratio of the first polarized light in the emitted light; and a ratio of the second polarized light in the transmitted light is larger than a ratio of the second polarized light in the emitted light. ### Claim 7 A display device comprising: a display panel; and an illumination device which illuminates the display panel, wherein the illumination device comprises: a light source unit which emits light toward the display panel; a modulation element located between the light source unit and the display panel, the modulation element comprising a modulation portion which modulates incident light, and a non-modulation portion which is adjacent to the modulation portion; and a liquid crystal element located between the light source unit and the modulation element, the liquid crystal element forming a lens between the light source unit and the modulation portion, wherein the modulation portion is smaller than the non-modulation portion, the modulation element comprises a third substrate comprising a plurality of third control electrodes, a fourth substrate comprising a fourth control electrode, and a second liquid crystal layer held between the third substrate and the fourth substrate, the second liquid crystal layer includes liquid crystal molecules twisted-aligned in a state where no electric field is formed between the third control electrodes and the fourth control electrode, the liquid crystal molecules in the non-modulation portion are vertically aligned by the electric field, the liquid crystal molecules in the modulation portion are twisted-aligned, and the modulation portion is arranged at a position where light is converged by the lens. ### Claim 8 (depends on 7) The display device of claim 7, further comprising a controller which controls the liquid crystal element, wherein the liquid crystal element comprises a first substrate comprising a plurality of first control electrodes, a second substrate comprising a second control electrode, and a first liquid crystal layer held between the first substrate and the second substrate, and the controller controls a voltage to be applied to the first liquid crystal layer for forming the lens which is opposed to the modulation portion in the first liquid crystal layer. ### Claim 9 (depends on 8) The display device of claim 8, wherein: each of the first control electrodes is a strip electrode; and the modulation portion is located between two first control electrodes. ### Claim 10 (depends on 7) The display device of claim 7, further comprising a controller which controls the modulation element, wherein the controller controls a voltage to be applied to the second liquid crystal layer for forming the modulation portion and the non-modulation portion in the second liquid crystal layer. ### Claim 11 (depends on 7) The display device of claim 7, wherein: a polarizer is nonexistent between the light source unit and the liquid crystal element; and a polarizer is nonexistent between the liquid crystal element and the modulation element. ### Claim 12 (depends on 11) The display device of claim 11, wherein: emitted light which is emitted from the light source unit, and transmitted light which is transmitted through the modulation element, include first polarized light and second polarized light, respectively; a ratio of the first polarized light in the transmitted light is smaller than a ratio of the first polarized light in the emitted light; and a ratio of the second polarized light in the transmitted light is larger than a ratio of the second polarized light in the emitted light. ### Claim 13 (depends on 7) The display device of claim 7, wherein the display panel includes a fifth substrate opposed to the illumination device, a sixth substrate, a third liquid crystal layer held between the fifth substrate and the sixth substrate, a pixel electrode and a common electrode which apply a voltage to the third liquid crystal layer, and a first optical element which is provided on the sixth substrate and transmits first polarized light. ### Claim 14 (depends on 13) The display device of claim 13, further comprising a second optical element which is provided on the fifth substrate, and transmits second polarized light intersecting the first polarized light. ### Claim 15 (depends on 7) The display device of claim 7, wherein the display panel includes a non-transmission portion overlapping the modulation portion, and a transmission portion overlapping the non-modulation portion.