×

Auto focus method for digital camera

  • US 20070110425A1
  • Filed: 12/14/2005
  • Published: 05/17/2007
  • Est. Priority Date: 11/11/2005
  • Status: Active Grant
First Claim
Patent Images

1. An auto focus method of a digital camera for moving a lens of said digital camera to the maximum focus value position, comprising steps of:

  • (a) calculating a focus value average FVavg of the focus values from the first step position to the Nth step position of said lens;

    (b) determining a lens movement state including a coarse state, a mid state and a fine state, wherein said lens moves A steps in said coarse state, B steps in said mid state and one step in said fine state, where B is less than A;

    (c) moving said lens and recording the focus value of said lens in said lens movement state according to said focus value average FVavg, a focus value difference FVdif, a previous maximum focus value FVmax, a coarse state threshold Tc, a mid state threshold Tm, a focus value difference threshold Tdif, a mid state count value MidCount and a downhill count value DownCount;

    (d) repeating steps (b) and (c) until the searching over a search range is finished; and

    (e) moving said lens to a right position corresponding to the maximum focus value.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×