Image display unit and method of detecting object

• US 20090033638A1
• Filed: 09/30/2008
• Published: 02/05/2009
• Est. Priority Date: 04/19/2005
• Status: Active Grant

• Current Assignee: Japan Display Incorporated
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Fujisawa, Hirotoshi, Harada, Tsutomu, Yamaguchi, Kazunori, Tateuchi, Mitsuru
• Granted Patent: US 8,907,928 B2
• Time in Patent Office: Days
• US Class Current: 345/176
• CPC Class Codes: G02F 1/13338 Input devices, e.g. touch panels
• CPC Class Codes: G02F 2203/11 involving infrared radiation
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/042 by opto-electronic means
• CPC Class Codes: G09G 2300/0452 Details of colour pixel setup, e.g. pixel composed of a red, a blue and two green components
• CPC Class Codes: G09G 2300/0842 forming a memory circuit, e.g. a dynamic memory with one capacitor
• CPC Class Codes: G09G 2310/0256 with the purpose of reversing the voltage across a light emitting or modulating element within a pixel
• CPC Class Codes: G09G 2360/145 the light originating from the display screen
• CPC Class Codes: G09G 3/3208 organic, e.g. using organic light-emitting diodes [OLED]
• CPC Class Codes: G09G 3/3225 using an active matrix
• CPC Class Codes: G09G 3/3648 using an active matrix G09G3/367 - G09G3/3696 take precedence
• CPC Class Codes: H10K 59/00 Integrated devices, or assemblies of multiple devices, comprising at least one organic light-emitting element covered by group H10K50/00
• CPC Class Codes: H10K 59/35 comprising red-green-blue [RGB] subpixels
• CPC Class Codes: H10K 59/351 comprising more than three subpixels, e.g. red-green-blue-white [RGBW]
• CPC Class Codes: H10K 59/38 comprising colour filters or colour changing media [CCM]
• CPC Class Codes: H10K 59/60 OLEDs integrated with inorganic light-sensitive elements, e.g. with inorganic solar cells or inorganic photodiodes

Abstract

An image display unit and a method of detecting an object which are capable of reliably detecting an object with a simple structure irrespective of use conditions are provided. Invisible light is emitted from a screen of a display portion. The invisible light reflected from a target object which comes in contact with or close to the screen is received on the screen. On the basis of the received invisible light, the target object is detected. Thus, the target object can be reliably detected without influence of the display state of the display portion, and influence of use conditions such as surrounding circumstances (the case where it is bright or dark). Moreover, for example, it is not necessary to separately arrange a component such as a touch panel, so the image display unit can be achieved with a simple structure.

Claims

1. An image display unit comprising:

a first light source emitting light in a visible wavelength range;

a second light source emitting light in an invisible wavelength range;

a plurality of liquid crystal devices arranged in a screen, the plurality of liquid crystal devices modulating light in a visible wavelength range from the first light source on the basis of image data and allowing light in an invisible wavelength range from the second light sources to pass through;

a plurality of light-receiving devices arranged in the screen, and receiving light in an invisible wavelength range;

a display driving means for driving the plurality of liquid crystal devices on the basis of the image data so that light in a visible wavelength range is emitted from the screen as display light;

a light reception driving means for driving the plurality of light-receiving devices so as to detect, on the screen, light in an invisible wavelength range emitted from the screen and reflected from a target object as detection light; and

a detecting means for detecting the target object on the basis of light reception signals obtained from the light-receiving devices,

wherein the liquid crystal devices each include;

a pair of transparent substrates facing each other,

a liquid crystal layer disposed between the pair of transparent substrates, and

a transmission filter allowing light in a predetermined wavelength range from light in a visible wavelength range and light in an invisible wavelength range having passed through the liquid crystal layer to pass through.

2. The image display unit according to claim 1, wherein

the light in the predetermined wavelength range is red light, green light, blue light or infrared light.

3. The image display unit according to claim 1, wherein

a transmission filter arranged in a region corresponding to the light-receiving device selectively allows infrared light to pass through.

4. The image display unit according to claim 1, wherein

at least one of the position and the size of the target object is detected on the basis of the detection light.

5. The image display unit according to claim 1, wherein

a plurality of target objects are detected on the basis of the detection light.

6. The image display unit according to claim 1, wherein

the plurality of liquid crystal devices and plurality of light-receiving devices are arranged in a matrix form,

the display driving means drives the plurality of liquid crystal devices so as to perform line-sequential display operation, and

the light reception driving means drives the plurality of light-receiving devices so as to perform line-sequential light reception operation.

7. The image display unit according to claim 6, wherein

the light reception driving means drives the plurality of light receiving devices so as to perform line-sequential light reception operation in synchronization with line-sequential display operation of the liquid crystal devices.

8. The image display unit according to claim 1, wherein

the plurality of light-receiving devices are also capable of receiving light in a visible wavelength range, and

the light reception driving means drives the plurality of light-receiving devices so as to also detect, on the screen, light in a visible wavelength range emitted from the screen and reflected from the target object as the detection light.

9. The image display unit according to claim 8, wherein

each of the plurality of light-receiving devices includes a first light-receiving device receiving light in a visible wavelength range and a second light-receiving device receiving light in an invisible wavelength range, and

the light reception driving means drives the first light-receiving device and the second light-receiving device so as to detect light in a visible wavelength range and light in an invisible wavelength range which are reflected from the target object, respectively.

10. The image display unit according to claim 9, wherein

the light reception driving means selectively switches the first light-receiving device or the second light-receiving device so as to receive light.

11. The image display unit according to claim 1, wherein

the plurality of light-receiving devices each include a silicon-based material.

12. An image display unit comprising:

a first light source emitting light in a visible wavelength range;

a second light source emitting light in an invisible wavelength range;

a plurality of liquid crystal devices arranged in a screen, the plurality of liquid crystal devices modulating light in a visible wavelength range from the first light source on the basis of image data and allowing light in an invisible wavelength range from the second light sources to pass through;

a plurality of light-receiving devices arranged in the screen, and receiving light in an invisible wavelength range;

a display driving unit for driving the plurality of liquid crystal devices on the basis of the image data so that light in a visible wavelength range is emitted from the screen as display light;

a light reception driving unit for driving the plurality of light-receiving devices so as to detect, on the screen, light in an invisible wavelength range emitted from the screen and reflected from a target object as detection light; and

a detecting unit for detecting the target object on the basis of light reception signals obtained from the light-receiving devices,

wherein the liquid crystal devices each include;

a pair of transparent substrates facing each other,

a liquid crystal layer disposed between the pair of transparent substrates, and

a transmission filter allowing light in a predetermined wavelength range from light in a visible wavelength range and light in an invisible wavelength range having passed through the liquid crystal layer to pass through.