Patent ID: 7801340

Claim:
A biometric information obtaining apparatus including: biometric information obtaining means for reading a living individual's body part during a relative movement between the body part and said biometric information obtaining means, and for obtaining a series of partial images of the body part as biometric information; velocity detecting means for detecting a movement velocity at which the body part moves with respect to said biometric information obtaining means; evaluating means for evaluating whether the movement velocity, which is detected by said velocity detecting means, exceeds an upper limit of a permissible range, which depends on property information of said biometric information obtaining means, or is lower than a lower limit of the permissible range; notifying means for notifying, if the above evaluation result of said evaluating means is that the movement velocity exceeds the upper limit of the permissible range or is lower than the lower limit of the permissible range, the evaluation result outside, movement amount detecting means for detecting, based on a relative positional relationship between two partial images successively obtained by said biometric information obtaining means, an amount of movement of the body part for a time interval at which such partial image is obtained by said biometric information obtaining means, and said velocity detecting means calculating said movement velocity based on the movement amount of the body part detected by said movement amount detecting means and the time interval at which such partial image obtaining is performed, wherein, if the movement amount detected by said movement amount detecting means is within a range of detection errors, said movement amount detecting means holds a former one of the two partial images, which are used in detecting the movement amount, as a reference image, and newly detects such movement amount of the body part based on a relative positional relationship between said reference image and another partial image obtained subsequently to a later one of the two partial images.