Digital camera and method of using same

• US 6,563,543 B1
• Filed: 03/31/1998
• Issued: 05/13/2003
• Est. Priority Date: 03/31/1998
• Status: Expired due to Term

• Current Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Original Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Inventors: Doron, Amir
• Primary Examiner(s): MOE, AUNG SOE
• Application Number:
  US09/053,819
• Time in Patent Office: 1,869 Days
• Field of Search: 348/362, 348/363, 348/364, 348/365, 348/366, 348/351, 348/357, 348/361, 348/345, 348/346, 348/348, 348/349, 348/229, 348/224, 348/213, 348/143, 348/207, 348/229.1, 348/224.1, 348/207.99, 396/63, 396/64, 396/65, 396/67, 396/72, 396/88, 396/89, 396/429, 396/431, 396/543
• US Class Current: 348/362
• CPC Class Codes: H04N 23/633 for displaying additional information relating to control or operation of the camera
• CPC Class Codes: H04N 23/673 based on contrast or high frequency components of image signals, e.g. hill climbing method
• CPC Class Codes: H04N 23/69 Control of means for changing angle of the field of view, e.g. optical zoom objectives or electronic zooming

Abstract

A camera which powers up in a default fixed-focus mode and has a capability whereby the photographer can select an auto-focus mode. The camera includes a lens, a shutter and a motor for moving the lens and for opening the shutter. A CCD, electrically interconnected to an analog to digital signal converter, receives image data and transforms the data to analogs for transmission to the converter where a digital output signals is generated. The digital signal is electrically transmitted to a processor which is electrically connected to the motor. In the camera default fixed focus mode, a first control algorithm facilitates a process wherein the processor generates an electrical signal to cause the motor to move the lens directly to a control position. To elect the auto-focus mode of camera operation, the photographer depresses a button and thereby selects a process which functions in accordance with the steps of a second control algorithm wherein the processor generates an electrical signal to cause the motor to move the lens past a focal point, and a second signal to cause the lens to backstep to the focal point. When the auto mode is selected, an icon appears on a data liquid crystal display (LCD) to indicate that auto focus mode is selected.

Claims

1. A digital camera including a housing and a lens having an adjustable aperture associated therewith for admitting light into said housing and onto an image sensing device for converting the light to an electrical signal, said camera comprising:

a) a camera setting adjustment system responsive to the electrical signal indicative of the object to be photographed for automatically adjusting the aperture to an optimal setting relative to an ambient lighting condition surrounding the object to be photographed;

b) a fixed focus mode algorithm for determining a focal point based on the adjusted aperture, for moving the lens to a focal point corresponding to said adjusted aperture, and for retaining the focal point corresponding to the adjusted aperture as a default setting; and

c) an automatic focus mode algorithm responsive to the optimal setting of the adjustable aperture for moving the lens to a determined focal point upon receipt of an externally generated activation command of said automatic focus mode algorithm.

2. A digital camera as claimed in claim 1 wherein the fixed focus mode algorithm is operable upon receipt of an externally generated activation command.

3. A digital camera as claimed in claim 1 wherein initial powering thereof is directed to the fixed focus mode algorithm.

4. A method of operating a digital camera having a housing and a lens having an adjustable aperture associated therewith for admitting light into said housing and onto an image sensing device for converting the light to an electrical signal, said camera comprising:

a) automatically adjusting the aperture to an optimal setting relative to an ambient lighting condition surrounding the object to be photographed;

b) determining a fixed-focus focal point based on the adjusted aperture, moving the lens to a fixed-focus focal point corresponding to the adjusted aperture, and retaining the fixed-focus focal point corresponding to the adjusted aperture as a fixed-focus default setting; and

c) determining an automatic-focus focal point based on the adjusted aperture and moving the lens to an automatic-focus focal point corresponding to the adjusted aperture.