Patent ID: 8130371
Filing Date: 2012-03-06
Classification: G01N

Abstract:
1. A method of calibrating a group of illuminating and light-receiving systems provided in a reflection characteristic measuring apparatus for a sheet specimen, said group of illuminating and light-receiving systems directing illuminating light onto a specimen surface of the sheet specimen and receiving reflected light from the specimen surface of the sheet specimen to measure the received reflected light, said method comprising the steps of: (a) measuring a first reference area included in a calibration reference plate with a first illuminating and light-receiving system included among said group of illuminating and light-receiving systems; (b) measuring a second reference area other than the first reference area included in the calibration reference plate with said first illuminating and light-receiving system; (c) calibrating said first illuminating and light-receiving system, based on a result of measurement of the first reference area in said step (a); (d) applying a result of calibration in said step (c) to determine a reflection characteristic of the second reference area from a result of measurement of the second reference area in said step (b); (e) measuring the second reference area with a second illuminating and light-receiving system other than said first illuminating and light-receiving system included among said illuminating and light-receiving systems; (f) calibrating said second illuminating and light-receiving system, based on the reflection characteristic determined in said step (d) and a result of measurement in said step (e); wherein the calibration reference plate in which the first reference area and the second reference area are arranged in a first direction, is used; wherein steps (a) and (b) are executed by transporting the calibration reference plate in the first direction to cause the first reference area and the second reference area to pass through a measurement area of said first illuminating and light-receiving system; and wherein step (e) is executed by transporting the calibration reference plate in a second direction to cause the second reference area to pass through a measurement area of said second illuminating and light-receiving system.