Light-emitting apparatus

• US 20050243237A1
• Filed: 04/22/2005
• Published: 11/03/2005
• Est. Priority Date: 04/30/2004
• Status: Active Grant

• Current Assignee: Citizen Electronics Company Limited
• Original Assignee: Citizen Electronics Company Limited
• Inventors: Sasuga, Masatoshi
• Granted Patent: US 7,538,830 B2
• Time in Patent Office: Days
• US Class Current: 349/57
• CPC Class Codes: F21S 41/00 Illuminating devices specially adapted for vehicle exteriors, e.g. headlamps reversing lights F21S43/00
• CPC Class Codes: F21S 41/141 Light emitting diodes [LED]
• CPC Class Codes: F21S 41/143 the main emission direction of the LED being parallel to the optical axis of the illuminating device
• CPC Class Codes: F21S 41/25 Projection lenses
• CPC Class Codes: F21S 41/285 Refractors, transparent cover plates, light guides or filters not provided in groups F21S41/24 - F21S41/2805
• CPC Class Codes: F21S 41/645 by electro-optic means, e.g. liquid crystal or electrochromic devices
• CPC Class Codes: F21S 43/14 Light emitting diodes [LED]
• CPC Class Codes: F21V 14/003 by interposition of elements with electrically controlled variable light transmissivity, e.g. liquid crystal elements or electrochromic devices
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: G02F 1/134309 characterised by their geometrical arrangement
• CPC Class Codes: G02F 1/29 for the control of the position or the direction of light beams, i.e. deflection
• CPC Class Codes: G02F 1/294 Variable focal length devices
• CPC Class Codes: G02F 2203/28 focussing or defocussing

Abstract

A light-emitting apparatus, comprising at least one LED element, and at least one liquid crystal lens disposed to face the LED element and positioned at a distance from the LED element, a focal length of light, broadening and narrowing directions of light, and changing the illuminating area of light being adjustable by applying a voltage to the at least one liquid crystal lens and a light-emitting apparatus, further comprising at least one lens placed on the liquid crystal lens.

Claims

1. A light-emitting apparatus, comprising:

at least one LED element; and

at least one liquid crystal lens disposed to face the LED element and positioned at a distance from the LED element.

3. The light-emitting apparatus according to claim 1,

wherein the LED element and the liquid crystal lens are supported by a case.

4. The light-emitting apparatus according to claim 3,

wherein the case has an LED-element-mounting surface for laying the LED element thereon, a lens-mounting surface for laying a peripheral portion of the liquid crystal lens thereon, and a reflecting surface extending from the LED-element-mounting surface to the lens-mounting surface.

6. The light-emitting apparatus according to claim 1,

further comprising a control device to apply a voltage to the liquid crystal lens.

8. The light-emitting apparatus according to claim 6,

wherein the liquid crystal lens has at least one electrode film, and

wherein the control device, including a variable voltage source for controlling the applied voltage, applies a voltage to the electrode film of the liquid crystal lens.

10. The light-emitting apparatus according to claim 1,

including one liquid crystal lens and a plurality of LED elements disposed to face the liquid crystal lens.

11. The light-emitting apparatus according to claim 1,

wherein a plurality of element and lens assemblies are supported by a case, and

wherein each of the plurality of element and lens assemblies includes at least one LED element and at least one liquid crystal lens.

2. A light-emitting apparatus, comprising:

at least one LED element;

at least one liquid crystal lens disposed to face the LED element and positioned at a distance from the LED element; and

at least one lens placed on the liquid crystal lens.

7. The light-emitting apparatus according to claim 2,

further comprising a control device to apply a voltage to the liquid crystal lens.

9. The light-emitting apparatus according to claim 7,

wherein the liquid crystal lens has at least one electrode film, and

wherein the control device, including a variable voltage source for controlling the applied voltage, applies a voltage to the electrode film of the liquid crystal lens.

5. A light-emitting apparatus, comprising:

at least one LED element;

at least one liquid crystal lens disposed to face the LED element and positioned at a distance from the LED element; and

at least one liquid crystal shutter placed on the liquid crystal lens.

12. A light-emitting apparatus, comprising:

at least one LED element having an emission surface;

at least one liquid crystal lens having two transparent boards, a liquid crystal layer inserted between the two transparent boards and electrodes provided on the inner surface of each transparent board and controlling the direction of liquid crystal molecules, and having a variable focal length; and

a case including a concave portion having a bottom surface, an opening and a reflecting surface provided on the inner surface of the concave surface,

the LED element being mounted on the bottom surface of the concave portion so that the emission surface is directed towards the opening of the concave portion, and the liquid crystal lens being disposed to face the LED element at a predetermined distance and supported on the opening of the concave portion.