Color temperature tuning method, color temperature tuning apparatus and display apparatus

Patent metadata

Field	Value
Publication number	US-9236026-B2
Application number	US-201314236217-A
Country	US
Kind code	B2
Filing date	May 27, 2013
Priority date	Mar 27, 2013
Publication date	Jan 12, 2016
Grant date	Jan 12, 2016

Abstract

Embodiments of the present invention relate to a color temperature tuning method, a color temperature tuning apparatus, and a display apparatus. The color temperature tuning method includes the steps of: matching an input color temperature signal with a color temperature value in the color temperature lookup table, and extracting a current signal corresponding to the color temperature value matching with the input color temperature signal from the color temperature lookup table; and controlling a light emitting device to emit light according to the current signal. According to embodiments of the present invention, intermediate calculation process is omitted and time for tuning the color temperature is shorten. Currents flowing through the blue and green light emitting elements are controlled to emit lights to excite red fluorescent powder, so that the LED emits lights having various color temperatures, and tuning accuracy of the color temperature and user experience are improved.

First claim

What is claimed is:

1. A color temperature tuning method, comprising following steps of:
S 1 : matching a input color temperature signal with a color temperature value in a color temperature lookup table, and extracting a current signal corresponding to the color temperature value matching with the input color temperature signal from in the color temperature lookup table; and
S 2 : controlling a light emitting device to emit light according to the current signal;
wherein the light emitting device comprises a blue light emitting element for emitting blue light and a green light emitting element for emitting green light,
the color temperature lookup table comprises a color temperature value, a ratio of a current flowing through the green light emitting element to a current flowing through the blue light emitting element; and
the S 2 further comprises: based on the current signal, applying the corresponding currents respectively to the green light emitting element and blue light emitting element to emit light.

2. The color temperature tuning method according to claim 1 , wherein before the step S 1 , the method further comprises a step of:
S 0 : creating a color temperature lookup table.

3. The color temperature tuning method according to claim 2 , wherein the step S 0 comprises steps of:
S 01 : establishing a calculation formula of a relationship between the current and the color temperature value by controlling the current applied to the light emitting device and measuring color temperature value corresponding to the current; and
S 02 : establishing the color temperature lookup table according to the calculation formula.

4. The color temperature tuning method according to claim 3 , wherein the calculation formula is:
T ( k )=[ t 6 ×k 6 −t 5 ×k 5 +t 4 ×k 4 −t 3 ×k 3 +t 2 ×k 2 −t 1 ×k+t 0 ],
where k denotes a ratio of a current flowing through a green light emitting element of the light emitting device to a current flowing through a blue light emitting element of the light emitting device, k=I(G chip ):I(B chip ), 0.25≦k≦2, t 0 ˜t 6 denotes coefficients of 0-6 order exponentials of k, I(G chip ) denotes a current flowing through the green light emitting element of the light emitting device, I(B chip ) denotes a current flowing through the blue light emitting element, and T(k) denotes the color temperature value corresponding to k.

5. A color temperature tuning apparatus for performing the color temperature tuning method according to claim 1 , the color temperature tuning apparatus comprising:
a color temperature controlling device for controlling the input color temperature signal and a light emitting device for emitting light according an output signal of the color temperature controlling device,
wherein the color temperature controlling device is connected with the light emitting device; and
the light emitting device comprises a light emitting unit, and the light emitting unit comprises a blue light emitting element for emitting blue light and a green light emitting element for emitting green light;
the color temperature controlling device comprises a color temperature lookup table unit for matching the color temperature signal with the color temperature value in the color temperature lookup table; the color temperature lookup table unit comprises a color temperature value and a ratio of a current flowing through the green light emitting element to a current flowing through the blue light emitting element; and
the color temperature controlling device, based on the corresponding current signal in the color temperature lookup table, which is matched to the input color temperature signal, respectively applies the corresponding currents to the green light emitting element and the blue light emitting element to emit light.

6. The color temperature tuning apparatus according to claim 5 , wherein the color temperature controlling device comprises:
a signal receiving unit for receiving the color temperature signal;
a color temperature selection unit for selecting the color temperature value proximate to the color temperature signal from the color temperature lookup table; and
a first power supply unit for supplying power to the signal receiving unit, the color temperature lookup table unit and the color temperature selection unit,
the signal receiving unit is connected with the color temperature lookup table unit, the color temperature lookup table unit is connected with the color temperature selection unit, the color temperature selection unit is connected with the light emitting device, and the first power supply unit is connected with the signal receiving unit, the color temperature lookup table unit, and the color temperature selection unit, respectively.

7. The color temperature tuning apparatus according to claim 6 , wherein the light emitting device comprises:
a current controlling unit for controlling the currents according to the output signal of the color temperature selection unit;
a second power supply unit for supplying power to the current controlling unit and the light emitting unit,
the current controlling unit is connected with the color temperature selection unit and the light emitting unit, respectively, the second power supply unit is connected with the current controlling unit and the light emitting unit, respectively.

8. The color temperature tuning apparatus according to claim 7 , wherein the second power supply comprises a first current output terminal and a second current output terminal.

9. The color temperature tuning apparatus according to claim 7 , wherein the light emitting unit is a LED.

10. The color temperature tuning apparatus according to claim 9 , wherein the LED comprises the blue light emitting element for emitting blue lights and a green light emitting element for emitting green lights, the blue light emitting element and the green light emitting element are connected with the first current output terminal and the second current output terminal, respectively.

11. The color temperature tuning apparatus according to claim 10 , wherein the LED comprises a red fluorescent powder.

12. A display apparatus comprising a color temperature tuning apparatus for performing the color temperature tuning method according to claim 1 ,
the color temperature tuning apparatus comprising:
a color temperature controlling device for controlling the input color temperature signal and a light emitting device for emitting light according an output signal of the color temperature controlling device,
wherein the color temperature controlling device is connected with the light emitting device; and
the light emitting device comprises a light emitting unit, the light emitting unit comprises a blue light emitting element for emitting blue light and a green light emitting element for emitting green light;
the color temperature controlling device comprises a color temperature lookup table unit for matching the color temperature signal with the color temperature value in the color temperature lookup table; the color temperature lookup table unit comprises a color temperature value and a ratio of a current flowing through the green light emitting element to a current flowing through the blue light emitting element;
the color temperature controlling device, based on the corresponding current signal in the color temperature lookup table, which is matched to the input color temperature signal, respectively applies the corresponding currents to the green light emitting element and the blue light emitting element to emit light.

13. The display apparatus according to claim 12 , where

Assignees

• Beijing Boe Display Tech Co
• Boe Technology Group Co Ltd

Inventors

• Jia Lili
• Chen Xiuyun
• Sun Lingyu
• Zhu Hongli
• Zhang Yu

Classifications

• G09G3/3413

  Details of control of colour illumination sources · CPC title

• G09G5/06 Primary

  using colour palettes, e.g. look-up tables · CPC title

• G09G2320/0666

  for control of colour parameters, e.g. colour temperature · CPC title