Control apparatus for optical density changing element

• US 20050254114A1
• Filed: 05/16/2005
• Published: 11/17/2005
• Est. Priority Date: 05/14/2004
• Status: Active Grant

• Current Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Original Assignee: Fuji Photo Film Co Limited (Fujifilm Holdings Corporation)
• Inventors: Ishii, Yoshio, Shinohara, Ryuji, Kaneiwa, Hideki, Matsunaga, Atsushi
• Granted Patent: US 7,474,453 B2
• Time in Patent Office: Days
• US Class Current: 359/265
• CPC Class Codes: G02B 13/0075 having an element with variable optical properties
• CPC Class Codes: G02B 5/205 Neutral density filters
• CPC Class Codes: G02B 5/24 Liquid filters G02B5/23 takes precedence
• CPC Class Codes: G02F 1/15 based on an electrochromic effect
• CPC Class Codes: G02F 1/1503 caused by oxidation-reduction reactions in organic liquid solutions, e.g. viologen solutions
• CPC Class Codes: G03B 19/04 Roll-film cameras
• CPC Class Codes: G03B 2219/045 adapted for unloading the film in the processing laboratory, e.g. disposable, reusable or recyclable cameras
• CPC Class Codes: G03B 7/08 Control effected solely on the basis of the response, to the intensity of the light received by the camera, of a built-in light-sensitive device
• CPC Class Codes: G03B 7/18 in accordance with light-reducing "factor" of filter or other obturator used with or on the lens of the camera
• CPC Class Codes: G03B 9/02 Diaphragms
• CPC Class Codes: H04N 23/55 Optical parts specially adapted for electronic image sensors; Mounting thereof
• CPC Class Codes: H04N 23/75 by influencing optical camera components

Abstract

An control apparatus for an optical density changing element comprising: an electromotive force generating element comprising an electromagnetic wave sensor (example: phototransistor) and a voltage source (example: battery), wherein the electromotive force generating element generates an electromotive force; an optical density changing element (light regulating filter) including an electrochromic material driven by the electromotive force; and a resistor connected in parallel to the optical density changing element.

Claims

1. An control apparatus for an optical density changing element comprising:

an electromotive force generating element comprising an electromagnetic wave sensor and a voltage source, wherein the electromotive force generating element generates an electromotive force;

an optical density changing element including an electrochromic material driven by the electromotive force; and

a resistor connected in parallel to the optical density changing element.

2. The control apparatus according to claim 1,

wherein the optical density changing element includes a nanoporous semiconductor material in which the electrochromic material is adsorbed, and the nanoporous semiconductor material has a roughness factor larger than 20.

3. The control apparatus according to claim 1,

wherein the optical density changing element in a color erased state has an optical density of 0.2 or less at a wavelength of 400 nm.

4. The control apparatus according to claim 1, wherein the optical density changing element in a color erased state has an average optical density of 0.1 or less in each of a wavelength range of 400 to 500 nm, a wavelength range of 500 to 600 nm and a wavelength range of 600 to 700 nm.

5. The control apparatus according to claim 1,

wherein the optical density changing element includes at least two electrochromic materials, and

wherein each of the at least two electrochromic materials independently has a wavelength where an electrochromic material generates a color so as to change an optical density.

6. The control apparatus according to claim 1,

wherein the electromagnetic wave sensor is a material of which resistance changes according to an intensity of an electromagnetic wave.

7. The control apparatus according to claim 1,

wherein the voltage source of the optical density changing element is a battery.

8. The control apparatus according to claim 1,

wherein the electromagnetic wave sensor is a phototransistor.