Liquid crystal shutter device for a camera

• US 20070115211A1
• Filed: 05/24/2006
• Published: 05/24/2007
• Est. Priority Date: 11/23/2005
• Status: Active Grant

• Current Assignee: Hon Hai Precision Industry Co., Ltd.
• Original Assignee: Hon Hai Precision Industry Co., Ltd.
• Inventors: Sun, Wen-Hsin
• Granted Patent: US 7,450,187 B2
• Time in Patent Office: Days
• US Class Current: 345/52
• CPC Class Codes: G02F 1/13378 by treatment of the surface, e.g. embossing, rubbing or light irradiation G02F1/133711, G02F1/133734, G02F1/133753 take precedence
• CPC Class Codes: G02F 1/133796 having conducting property
• CPC Class Codes: G02F 2201/58 Arrangements comprising a monitoring photodetector
• CPC Class Codes: G02F 2203/48 Variable attenuator
• CPC Class Codes: G03B 9/08 Shutters

Abstract

A liquid crystal shutter (100) and a camera (200) with therein. The liquid crystal shutter (100) includes a power supply (10), a switch (20) and a liquid crystal box (40), all parts are electrically connected and form a control circuit. The liquid crystal box (40) includes a first electric plate (42), a first polarizing filter (424), a second electric plate (44), and a second polarizing filter (444). A predetermined amount of liquid crystal (46) is contained between the first electric plate (42) and the second electric plate (44). The first polarizing filter (424) is formed on a surface of the first electric plate (42). A second polarizing filter (444) is formed on a surface of the second electric plate (44). The axial direction of the second polarizing filter (444) is perpendicular to that of the first polarizing filter (424).

Claims

1. A liquid crystal shutter device for a camera, comprising:

a power supply;

a switch;

a liquid crystal box connected to the power supply and the switch, the liquid crystal box including;

a first electric plate, including a first transparent base and a first transparent electroplated layer, the first base being coated with the first electroplated layer;

a first polarizing filter formed on a surface of the first electric plate;

a second electric plate parallel to the first electric plate, the second electric plate including a second transparent base and a second transparent electroplated layer, the second base being coated with the second electroplated layer;

a second polarizing filter, the axial direction of the second polarizing filter being perpendicular to that of the first polarizing filter, the second polarizing filter being formed on a surface of the second electric plate;

and

a predetermined amount of liquid crystal contained between the first electric plate and the second electric plate;

wherein the power supply, the switch, and the liquid crystal box are electrically connected in series and form a control circuit.

2. The liquid crystal shutter device as claimed in claim 1, wherein the first and second bases are made of glass.

3. The liquid crystal shutter device as claimed in claim 1, wherein the first and second electroplated layers are made of an oxide of indium and tin.

4. The liquid crystal shutter device as claimed in claim 1, wherein the first electric plate defines a plurality of first parallel grooves.

5. The liquid crystal shutter device as claimed in claim 4, wherein the direction of the first parallel grooves of the first electric plate is the same as the axial direction of the first polarizing filter.

6. The liquid crystal shutter device as claimed in claim 5, wherein the second electric plate defines a plurality of second parallel grooves.

7. The liquid crystal shutter device as claimed in claim 6, wherein the direction of the second parallel grooves of the second electric plate is the same as the axial direction of the second polarizing filter.

8. The liquid crystal shutter device as claimed in claim 1, wherein the liquid crystal shutter device further comprises a rheostat capable of adjusting the voltage difference between the first electric plate and the second electric plate.

9. The liquid crystal shutter device as claimed in claim 1, wherein the liquid crystal is made of nematic phase material.

10. The liquid crystal shutter device as claimed in claim 9, wherein the liquid crystal is selected from the group consisting of lithium niobate, lithium molybdate, and potassium dihydrogen phosphate.

11. A camera comprising:

a lens module; and

a liquid crystal shutter located in front of the lens module, the liquid crystal shutter including;

a power supply;

a switch;

a liquid crystal box connected to the power supply and the switch, the liquid crystal box including;

a first electric plate;

a first polarizing filter formed on a surface of the first electric plate;

a second electric plate parallel to the first electric plate;

a second polarizing filter, the axial direction of the second polarizing filter being perpendicular to that of the first polarizing filter, the second polarizing filter being formed on a surface of the second electric plate;

and

a predetermined amount of liquid crystal contained between the first electric plate and the second electric plate;

wherein the power supply, the switch, and the liquid crystal box are electrically connected in series and form a control circuit, and wherein the control circuit further includes a rheostat capable of adjusting the voltage between the first electric plate and the second electric plate.

12. The camera as claimed in claim 11, wherein at least one of the first and second electric plates comprises a base and an electroplated layer, the base being coated with the electroplated layer.

13. The camera as claimed in claim 12, wherein the electroplated layer is made of an oxide of indium and tin.

14. The camera as claimed in claim 13, wherein the first electric plate has a plurality of first parallel grooves, the direction of the first parallel grooves of the first electric plate being the same as the axial direction of the first polarizing filter.

15. The camera as claimed in claim 14, wherein the second electric plate has a plurality of second parallel grooves, the direction of the second parallel grooves of the second electric plate being the same as the axial direction of the second polarizing filter.

16. A liquid crystal shutter device for a camera, comprising:

a first transparent electric plate with a plurality of first parallel grooves formed in one surface thereof;

a first transparent polarizing filter formed an opposite surface of the first electric plate, the first polarizing filter having a first optical axis parallel to the first grooves;

a second transparent electric plate spaced from and parallel to the first electric plate, the second electric plate having a plurality of second parallel grooves formed in one surface thereof, the second grooves being substantially perpendicular to the first grooves, the surfaces of the first and second electric plates that form the first and second grooves facing each other;

a second transparent polarizing filter formed on an opposite surface of the second electric plate, the second polarizing filter having a second optical axis parallel to the second grooves;

a predetermined amount of liquid crystal molecules contained between the first electric plate and the second electric plate; and

a switch circuit connected to the first and second electric plates so as to selectively establish an electric field between the first and second electric plates for changing a direction of the liquid crystal molecules, thereby selectively allowing the rays of light to pass through and stopping the rays of light from passing through the first and second polarizing filters.

17. The liquid crystal shutter device as claimed in claim 16, wherein the first and second bases are made of glass.

18. The liquid crystal shutter device as claimed in claim 16, wherein the first and second electroplated layers are made of an oxide of indium and tin.

19. The liquid crystal shutter device as claimed in claim 16, wherein the liquid crystal shutter device further comprises a rheostat capable of adjusting the voltage difference between the first electric plate and the second electric plate.

20. The liquid crystal shutter device as claimed in claim 16, wherein the liquid crystal is made of nematic phase material.