Camera

• US 5,134,435 A
• Filed: 04/10/1991
• Issued: 07/28/1992
• Est. Priority Date: 04/25/1985
• Status: Expired due to Term

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Kobe, Takashi, Tsuboi, Takayuki
• Primary Examiner(s): ADAMS JR, RUSSELL E
• Application Number:
  US07/683,103
• Time in Patent Office: 475 Days
• Field of Search: 354/434-437, 354/429, 354/439-446, 354/451, 354/452, 354/458, 354/484, 354/173.1
• US Class Current: 396/169
• CPC Class Codes: G03B 2217/005 Blur detection
• CPC Class Codes: G03B 9/60 by varying speed of movement of obturating members
• CPC Class Codes: G03B 9/70 with flash-synchronising contacts

Abstract

A camera including shutter blades; a driving device which, upon receipt of electric energy, drives the shutter blades to open; an optical detecting device for optically detecting the operating state of the shutter blades; and a control circuit which controls the opening speed of the shutter blades by changing the amount of electric energy supplied to the driving device in response to the output of the optical detecting device.

Claims

1. A camera comprising:

(a) shutter blades;

(b) driving means for driving said shutter blades, said driving means being arranged to drive said shutter blades to open when driving means is energized;

(c) optical detecting means for optically detecting an operating state of said shutter blades; and

(d) control means for controlling an opening speed of said shutter blades by varying an amount of electric energy supplied to said driving means in response to an output of said optical detecting means, said control means including switching means for changing the opening speed of said shutter blades from one speed to another and shifting means for shifting a position of said switch means to lower the opening speed of said shutter blades in the event of flash photographing.

2. A camera comprising:

(a) shutter blades;

(b) driving means for driving said shutter blades;

said driving means being arranged to drive said shutter blades to open when driving means is energized;

(c) optical detecting means for optically detecting an operating state of said shutter blades; and

(d) control means for controlling an opening speed of said shutter blades by varying an amount of electric energy supplied to said driving means in response to an output of said optical detecting means, said control means including switching means for changing the opening speed of said shutter blades from one speed to another and brightness discriminating means for shifting a position of said switch means to change the opening speed of said shutter blades according to a brightness of external light in a flash photographing mode, wherein said brightness discriminating means includes shifting means for shifting the position of said switch means to lower the opening speed of said shutter blades in response to darkness of the external light.

3. A camera, comprising:

(a) shutter blades;

(b) driving means for driving said shutter blades, said driving means being arranged to drive said shutter blades to open when driving means is energized;

(c) optical detecting means for optically detecting an operating state of said shutter blades; and

(d) control means for controlling an opening speed of said shutter blades by varying an amount of electric energy supplied to said driving means in response to an output of said optical detecting means;

(e) abnormal state detecting means for detecting an abnormal operation of the shutter blades in response to the output of the optical detecting means; and

(f) prohibition means for prohibiting operations of the camera in response to the detection of the abnormal operation of the shutter by the abnormal state detecting means.

4. A camera according to claim 3, wherein said abnormal state detecting means includes a timer means for detecting the speed of the shutter blades.

5. A camera comprising:

(A) shutter blades;

(B) driving means for driving the shutter blade, said driving means driving the shutter blades to open upon application of current thereto; and

(C) control means for changing an opening speed of the shutter blades by changing a amount of current applied to the driving means, said control means controlling the opening speed of the shutter blades lower in flash photography than in normal photography.

6. A camera according to claim 5, wherein said control means includes shifting means for shifting the opening speed of the shutter blades to be higher when field brightness is bright in the flash photography than when the field brightness is dark.

7. A camera according to claim 5, wherein said optical detecting means includes a photo-interrupter.