Light modulation information display device and illumination control device

• US 20020018053A1
• Filed: 04/30/2001
• Published: 02/14/2002
• Est. Priority Date: 05/02/2000
• Status: Active Grant

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Kyomoto, Tadao
• Granted Patent: US 6,956,555 B2
• Time in Patent Office: Days
• US Class Current: 345/204
• CPC Class Codes: G09G 2310/024 Scrolling of light from the illumination source over the display in combination with the scanning of the display screen
• CPC Class Codes: G09G 2310/08 Details of timing specific for flat panels, other than clock recovery
• CPC Class Codes: G09G 3/342 using several illumination sources separately controlled corresponding to different display panel areas, e.g. along one dimension such as lines
• CPC Class Codes: H01J 61/025 Associated optical elements
• CPC Class Codes: H01J 61/70 Lamps with low-pressure unconstricted discharge having a cold pressure < 400 Torr
• CPC Class Codes: H01J 61/92 Lamps with more than one main discharge path

Abstract

An illumination control device for illuminating an light modulation information display device with light includes: at least one illumination device for irradiating light which is generated through discharging; and a driving waveform generation section for controlling the light which is irradiated from the at least one illumination device to the light modulation information display device. The light modulation information display device is operable so as to have a first period and a second period during which an image is displayed. During the first period, the driving waveform generation section applies a first voltage to the at least one illumination device, the first voltage causing the at least one illumination device to be turned entirely-ON. During the second period, the driving waveform generation section applies a second voltage to at least a portion of the at least one illumination device.

Claims

1. An illumination control device for illuminating an light modulation information display device with light, comprising:

at least one illumination device for irradiating light which is generated through discharging; and

a driving waveform generation section for controlling the light which is irradiated from the at least one illumination device to the light modulation information display device,

wherein;

the light modulation information display device is operable so as to have a first period and a second period during which an image is displayed;

during the first period, the driving waveform generation section applies a first voltage to the at least one illumination device, the first voltage causing the at least one illumination device to be turned entirely-ON; and

during the second period, the driving waveform generation section applies a second voltage to at least a portion of the at least one illumination device.

2. An illumination control device according to claim 1,

wherein the second voltage is a partially-ON voltage for causing at least a portion of the at least one illumination device to be illuminated.

3. An illumination control device according to claim 1,

wherein the second voltage causes the at least one illumination device to have a minimal discharging.

4. An illumination control device according to claim 1,

wherein the second voltage causes the at least one illumination device to retain a partial discharging.

5. An illumination control device according to claim 1, wherein:

each of the at least one illumination device comprises two main discharging electrodes and a partial discharging electrode provided in a vicinity of one of the two main discharging electrodes;

the driving waveform generation section applies the first voltage between the two main discharging electrodes during the first period; and

the driving waveform generation section applies the second voltage between the partial discharging electrode and the one main discharging electrode in the vicinity of the partial discharging electrode during the second period.

6. An illumination control device according to claim 5, wherein:

the at least one illumination device comprises a plurality of illumination devices; and

for each of the plurality of illumination devices, the driving waveform generation section individually selects a voltage to be applied and electrodes between which a discharge is to occur, depending on the first period and the second period of the illumination device.

7. An illumination control device according to claim 5,

wherein an outer wall of the illumination device comprises at least one of a light shielding surface or an ultraviolet ray-shielding surface in a vicinity of a portion between the one main discharging electrode and the partial discharging electrode.

8. A light modulation information display device comprising:

the illumination control device according to claim 1;

and

a light modulation information display section,

wherein the light modulation information display section controls light provided from the illumination control device to display information.

9. A light modulation information display device according to claim 8, wherein the controlling of the light comprises at least one of transmission, absorption, interception, reflection of the light.

10. A light modulation information display device comprising:

a light modulation information display section; and

an illumination control device comprising at least one illumination device having two main discharging electrodes and a partial discharging electrode, wherein light provided from the at least one illumination device is irradiated to the light modulation information display section, wherein;

the at least one illumination device has a length greater than a corresponding dimension of the light modulation information display section;

the at least one illumination device includes a first region corresponding to the light modulation information display section and a second region not corresponding to the light modulation information display section; and

one of the two main discharging electrodes is disposed in the first region, and the other of the two main discharging electrodes and the partial discharging electrode are disposed in the second region.

11. A light modulation information display device according to claim 10, wherein:

the at least one illumination device undergoes a partially-ON state between the other of the two main discharging electrodes disposed in the second and the partial discharging electrode.

12. A light modulation information display device according to claim 10,

wherein the at least one illumination device retains a minimal discharging between the other of the two main discharging electrodes disposed in the second region and the partial discharging electrode.

13. A light modulation information display device according to claim 10, wherein the at least one illumination device retains a partial discharging between the other of the two main discharging electrodes disposed in the second region and the partial discharging electrode.

14. A light modulation information display device according to claim 10, wherein:

the light modulation information display section is split into a plurality of split display regions each containing a number of horizontal scanning lines;

at least one split activatable region is provided in the illumination control device so as to correspond to each of the plurality of split display regions, wherein at least one illumination device is assigned to each of the plurality of split activatable regions;

a voltage is applied between the two main discharging electrodes of at least one illumination device in at least one of the plurality of split activatable regions corresponding to at least one of the plurality of split display regions over which scanning of an image has progressed or completed; and

a voltage is applied between the partial discharging electrode and the other of the two main discharging electrodes of at least one illumination device in at least one of the plurality of split activatable regions corresponding to at least one split display region over which scanning of the image has not been performed.

15. A light modulation information display device according to claim 10, wherein:

the light modulation information display device further includes a light modulation material;

the light modulation information display section is split into a plurality of split display regions each containing a number of horizontal scanning lines;

at least one split activatable region is provided in the illumination control device so as to correspond to each of the plurality of split display regions, wherein at least one illumination device is assigned to each of the plurality of split activatable regions;

after scanning of an image over at least one of the plurality of split display regions has progressed or completed, with a delay corresponding to a response time of the light modulation material, a voltage is applied between the two main discharging electrodes of at least one illumination device in at least one of the plurality of split activatable regions corresponding to the at least one split display region; and

a voltage is applied between the partial discharging electrode and the other of the two main discharging electrodes of at least one illumination device in at least one of the plurality of split activatable regions corresponding to the split display regions over which scanning has not been performed.

16. A light modulation information display device according to claim 15,

wherein the light modulation information display device further includes a light-switching element for controlling the light modulation information display section:

and

after the scanning has progressed or completed, with a delay corresponding to a response time of the light modulation material and a response time of the light-switching element, a voltage is applied between the two main discharging electrodes of at least one illumination device in the at least one split activatable region corresponding to the at least one split display region.

17. A light modulation information display device according to claim 10, wherein:

based on an information displaying signal which is applied to the light modulation information display section during a 1 frame, a voltage is applied between the two main discharging electrodes of the at least one illumination device during an entirely-ON voltage period,

a voltage is applied between the partial discharging electrode and the other of the two main discharging electrodes of the at least one illumination device during a partially-ON voltage period or a retention discharging voltage period.

18. A light modulation information display device according to claim 15, wherein:

when a period during which the voltage is applied between the other of the two main discharging electrodes and the partial discharging electrode transitions to a period during which the voltage is applied between the two main discharging electrodes, a delay corresponding to a response time of the light modulation material is introduced in the split activatable region after scanning over an image has progressed or completed in the light modulation information display section.