| 摘要 |
A first optical sensor captures an image with a two-dimensional region in an object to be measured as the measurement range thereof. A second optical sensor outputs a signal indicating the brightness of a spot region included in the two-dimensional region. A second measurement unit measures the flicker period of the object to be measured using the second optical sensor. With the reciprocal of a frame rate as a frame time, a setting unit sets the frame rate at which a value obtained by multiplying the flicker period by an integer of 1 or more is defined as the frame time when an exposure time is longer than or equal to the flicker period, and sets the frame rate at which a value obtained by dividing the flicker period by an integer greater than 1 is defined as the frame time when the exposure time is shorter than the flicker period. A first measurement unit measures a characteristic relating to the color of the two-dimensional region using the first optical sensor under the set frame rate. |
