LED bar

• US 8,287,144 B2
• Filed: 09/05/2008
• Issued: 10/16/2012
• Est. Priority Date: 09/05/2007
• Status: Active Grant

• Current Assignee: Harman Professional Denmark ApS. (Samsung Electronics Co. Ltd.)
• Original Assignee: Martin Professional A/S (Samsung Electronics Co. Ltd.)
• Inventors: Pedersen, Allan, Chen, Xia, Li, Guohui, Liang, Chen
• Primary Examiner(s): Sawhney, Hargobind S
• Application Number:
  US12/676,667
• Publication Number:
  US 20100295468A1
• Time in Patent Office: 1,502 Days
• Field of Search: 362/218, 362/217.01, 362/217.02, 362/219, 362221-224, 362/227, 362/231, 362/238, 362/249.02, 362/249.01, 362/276, 362/294, 362/326, 362/330, 362/333, 362/336, 362/337, 362/338, 362/544, 362/545, 362/800, 340/4.3, 340/815.45
• US Class Current: 362/217.01
• CPC Class Codes: F21S 10/02 changing colors F21S10/002 - F21S10/007, F21S10/04 take precedence
• CPC Class Codes: F21S 4/28 rigid, e.g. LED bars
• CPC Class Codes: F21V 13/04 the elements being reflectors and refractors for vehicle rear lights F21S43/40
• CPC Class Codes: F21V 21/30 Pivoted housings or frames
• CPC Class Codes: F21V 23/06 the elements being coupling devices , e.g. connectors
• CPC Class Codes: F21V 29/507 of means for protecting lighting devices from damage, e.g. housings
• CPC Class Codes: F21V 29/74 with fins or blades
• CPC Class Codes: F21V 29/83 the elements having apertures, ducts or channels, e.g. heat radiation holes
• CPC Class Codes: F21V 31/03 with provision for venting for vehicle head lights F21S45/33; for vehicle rear lights F21S41/192
• CPC Class Codes: F21Y 2103/10 comprising a linear array of point-like light-generating elements
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: H05B 45/00 Circuit arrangements for operating light-emitting diodes [LED]
• CPC Class Codes: H05B 45/20 Controlling the colour of the light

Abstract

The present invention relates to LED bar modules where the LED groups are placed at a pixel board. The present invention further concerns a method for calibration of LEDs. It is the object of the invention to achieve a highly efficient LED bar for generating a bar of light. A further object of the invention is to store calibration data for each LED both electrically and mechanically close to the actual LED. Preferably, the main printed circuit is placed inside a heat conductive tube, where the pixel board is placed outside the heat conductive tube in a longitudinal recess, where the main printed circuit is placed inside an isolation cover. Hereby, it is achieved that the LEDs are placed on the outside of the tube in a way where heat generated from the LEDs is conducted downwards to the tube. Inside the tube, the rest of the power electronics and also the light controlling electronics are placed.

Claims

1. LED bar modules (2) comprising a number of LED groups, which LED groups comprise a number of LEDs (54), which LEDs (54) have different colours, which LEDs (54) are electrically connected to a colour controller for generating light with changing colours, which colour controller is connected to a power supply, where the power supply is formed at a main printed circuit (8), where the LED groups are placed at a pixel board (6), which pixel board (6) conducts heat from the LEDs (54), characterized in that the main printed circuit (8) is placed inside a heat conductive tube (4), where the pixel board (6) is placed outside the heat conductive tube (4) in a longitudinal recess (14), where a connector is electrically connecting the pixel board (6) to the main printed circuit (8), where the main printed circuit (8) is placed inside an isolation cover (12), which isolation cover (12) is placed between the main printed circuit (8) and the heat conductive tube (4), which isolation cover (12) has a longitudinal opening for achieving heat conduction between the main printed circuit (8) and a central part (16) of the upper wall of the heat conductive tube (4).

2. LED bar modules according to claim 1, characterized in that the colour controller is placed at a daughter printed circuit (10), which daughter printed circuit (10) is electrically and mechanically connected to the main printed circuit (8) by connectors (18).

3. LED bar modules according to claim 1 or 2, characterized in that the pixel board (6) comprises a memory circuit (53,55), in which memory circuit (53,55) LED calibration data for the LEDs (54) at the pixel board (6) are stored.

4. LED bar module according to claim 1 or 2, characterized in that the LEDs (54) are formed at a chip, which chip further comprises a memory circuit for storing calibration data for the actual LED.

5. LED bar modules according to claim 1, characterized in that a number of LED modules are connected in order to form a longitudinal LED bar, where each LED bar module comprises female connectors at the first end and male connectors at the second end, which connectors comprise a first group of power connectors and a second group of data connectors.

6. LED bar modules according to claim 5, characterized in that two independent data buses are connected between the modules.

7. LED bar modules according to claim 1, characterized in that the LED groups are placed beneath lenses for deflecting generated light in a mainly perpendicular and longitudinal direction of the bar.

8. LED bar modules according to claim 6, characterized in that the lenses are placed in relation to reflectors, which reflectors deflect the light in a mainly perpendicular and longitudinal direction in relation to the bar.

9. LED bar modules according to claim 1, further comprising a plurality of colour groups, where each colour group comprises at least at least one of said LEDs, where the colour groups are connected to control means, which control means control has means for controlling at least one physical parameter used in relation to the operation of the colour groups, and where each colour group is connected to a control circuit, characterized in that calibration data for a colour group is stored in a calibration memory, where said control means is adapted to control each colour group in accordance with local, stored calibration data during operation.

10. LED bar modules according to claim 9, characterized in that the stored calibration data comprises, for each LED, at least operational time in relation to the actual LED power level.

11. LED bar modules according to claim 10, characterized in that the operational time in relation to the actual power level is stored in a two-dimensional historic file in the calibration data storage.