摘要:
An optical reading including a device for effecting discrimination between a dither-matrix reading area and a non-dither-matrix reading area on a subject copy, an irradiating device for irradiating local segments of the subject copy with light beams having different intensities, a reading device for obtaining image data representative of the presence or absence of an achromatic tone in each local segment based on an amount of the light beam reflected by each local segment, a control device for operating the irradiating and reading devices to irradiate the local segments in a predetermined discriminating zone of the subject copy with the light beams having different intensities at different times, to obtain first and second image data, a device for comparing the first and second image data of each local segment in the discrimination zone, to determine whether the first and second image data agree with each other or not for each local segment, and a device for determining that the discrimination zone is the dither-matrix reading area, if a degree of disagreement of the first and second image data exceeds a predetermined reference value, and determining that the discrimination zone is the non-dither-matrix reading area, if the degree of disagreement does not exceed the reference value.
摘要:
An optical image reading apparatus for photoelectrically reading images formed in at least two colors on a surface of an original having a base color different from the at least two colors, including a first reading device for obtaining a first image signal for each of a multiplicity of reading spots in a predetermined area on the original. The first image signal has two different levels one of which corresponds to the base color and the other of which corresponds to the at least two colors. The apparatus further includes a second reading device for obtaining a second image signal for the each reading spot. The second image signal cooperates with the first image signal to discriminate each of the at least two colors from the other of the at least two colors. Provisions are made for determining whether the levels of the first image signals for all of the multiplicity of reading spots are equal to the above-indicated one level corresponding to the base color, or not. If so, the second reading device is inhibited from operating to obtain the second inage signal for each reading spot.