Backlight module transmitting electricity through magnetic field induction

• US 9,148,913 B2
• Filed: 05/17/2013
• Issued: 09/29/2015
• Est. Priority Date: 09/19/2012
• Status: Active Grant

• Current Assignee: AU Optronics Corporation
• Original Assignee: AU Optronics Corporation
• Inventors: Lee, Tsung-Shiun, Lin, Huang-Ti, Hsu, Bing-Shiang
• Primary Examiner(s): Wells, Kenneth B
• Application Number:
  US13/896,330
• Publication Number:
  US 20140077698A1
• Time in Patent Office: 865 Days
• Field of Search: 315/185.R, 315/219, 315/291, 315/294, 315/312, 345/102
• US Class Current: 1/1
• CPC Class Codes: H05B 45/20 Controlling the colour of the light
• CPC Class Codes: H05B 45/30 Driver circuits

Abstract

A backlight module is provided, which includes a first coil, a first driving circuit, a second coil, a rectifying circuit and a light emitting unit. The first driving circuit is electrically connected to the first coil for controlling the first coil to produce a first magnetic field. The second coil is disposed on a transmission direction of the first magnetic field corresponding to the first coil for receiving the first magnetic field and providing a first induction voltage according to the first magnetic field. The rectifying circuit is electrically connected to the second coil for converting the first induction voltage into a first driving voltage. The light emitting unit is electrically connected to the rectifying circuit to provide a backlight according to the first driving voltage.

Claims

1. A backlight module, comprising:

a first coil;

a first driving circuit, electrically connected to the first coil for controlling the first coil to produce a first magnetic field;

a second coil, configured to receive the first magnetic field and providing a first induction voltage according to the first magnetic field;

a rectifying circuit, electrically connected to the second coil for converting the first induction voltage into a first driving voltage;

a light emitting unit, electrically connected to the rectifying circuit to provide a backlight according to the first driving voltage; and

a first substrate having a first surface and a second surface opposite to the first surface, wherein the first coil and the first driving circuit are disposed at a side of the first substrate the same as the first surface, and the second coil, the rectifying circuit and the light emitting unit are disposed at another side of the first substrate the same as the second surface,

wherein the light emitting unit comprises a light emitting diode light bar, and the second coil is disposed at a second substrate of the light emitting diode light bar.

2. The backlight module as claimed in claim 1, wherein the first coil is a coil pattern printed on the first substrate, and the second coil is a coil pattern printed on a second substrate of the light emitting diode light bar.

3. The backlight module as claimed in claim 1, wherein the rectifying circuit is electrically connected between the second coil and the light emitting diode light bar and comprises:

a first diode, wherein anode of the first diode is electrically connected to first terminal of the second coil;

a second diode, wherein cathode of the second diode is electrically connected to the anode of the first diode;

a third diode, wherein anode of the third diode is electrically connected to second terminal of the second coil and cathode of the third diode is electrically connected to the cathode of the first diode;

a fourth diode, wherein cathode of the fourth diode is electrically connected to the anode of the third diode and anode of the fourth diode is electrically connected to the anode of the second diode; and

a first capacitor, electrically connected between the cathode of the first diode and the anode of the second diode for providing the first driving voltage.

4. The backlight module as claimed in claim 1, further comprising:

a third coil, electrically connected to the first driving circuit and producing a second magnetic field under controlling of the first driving circuit; and

a fourth coil, electrically connected to the rectifying circuit, configured to receive the second magnetic field and provide a second induction voltage to the rectifying circuit according to the second magnetic field;

wherein the rectifying circuit converts the second induction voltage into a second driving voltage, and the light emitting unit provides the backlight according to the first driving voltage and the second driving voltage.

5. A backlight module, comprising:

a first coil;

a first driving circuit, electrically connected to the first coil for controlling the first coil to produce a first magnetic field, and configured for receiving a switch driving signal and the first driving circuit;

a second coil, configured to receive the first magnetic field and providing a first induction voltage according to the first magnetic field;

a rectifying circuit, electrically connected to the second coil for converting the first induction voltage into a first driving voltage;

a light emitting unit, electrically connected to the rectifying circuit to provide a backlight according to the first driving voltage; and

a first substrate having a first surface and a second surface opposite to the first surface, wherein the first coil and the first driving circuit are disposed at a side of the first substrate the same as the first surface, and the second coil, the rectifying circuit and the light emitting unit are disposed at another side of the first substrate the same as the second surface,

wherein the first driving circuit comprises;

a voltage source, electrically connected to first terminal of the first coil for providing a first voltage to the first terminal of the first coil;

a first switching component, electrically connected between second terminal of the first coil and a second voltage for providing the second voltage to the second terminal of the first coil according to the switch driving signal; and

a second switching component, electrically connected between the first terminal and the second terminal of the first coil and turned on according to inverse signal of the switch driving signal,

wherein the first switching component comprises a first transistor, first terminal of the first transistor is electrically connected to the second terminal of the first coil, second terminal of the first transistor receives the second voltage and control terminal of the first transistor receives the switch driving signal, and

wherein the second switching component comprises a second transistor, first terminal of the second transistor is electrically connected to the first terminal of the first coil, second terminal of the second transistor is electrically connected to the second terminal of the first coil and control terminal of the second transistor receives the inverse signal of the switch driving signal.

6. A backlight module, comprising:

a first coil;

a first driving circuit, electrically connected to the first coil for controlling the first coil to produce a first magnetic field;

a second coil, configured to receive the first magnetic field and providing a first induction voltage according to the first magnetic field;

a rectifying circuit, electrically connected to the second coil for converting the first induction voltage into a first driving voltage;

a light emitting unit, electrically connected to the rectifying circuit to provide a backlight according to the first driving voltage; and

a first substrate having a first surface and a second surface opposite to the first surface, wherein the first coil and the first driving circuit are disposed at a side of the first substrate the same as the first surface, and the second coil, the rectifying circuit and the light emitting unit are disposed at another side of the first substrate the same as the second surface,

wherein the first driving circuit is also used to receive a switch driving signal and the first driving circuit comprises;

a voltage source for providing a first voltage;

a first switching component, electrically connected between the voltage source and first terminal of the first coil for providing the first voltage to the first terminal of the first coil according to the switch driving signal; and

a second switching component, electrically connected between the first terminal and second terminal of the first coil and turned on according to inverse signal of the switch driving signal.

7. The backlight module as claimed in claim 6, wherein the first switching component comprises a first transistor, first terminal of the first transistor is electrically connected to the voltage source, second terminal of the first transistor is electrically connected to the first terminal of the first coil and control terminal of the first transistor receives the switch driving signal;

the second switching component comprises a second transistor, first terminal of the second transistor is electrically connected to the first terminal of the first coil, second terminal of the second transistor is electrically connected to the second terminal of the first coil and control terminal of the second transistor receives the inverse signal of the switch driving signal.

8. The backlight module as claimed in claim 6, wherein the switch driving signal is provided by a control chip, the control chip comprises a timing controller and the switch driving signal is provided by the timing controller.