Patent ID: 9435731
Filing Date: 2016-09-06
CPC Classification: G01J,G01N

Claim Text:
1. A method for detecting a light that has passed through a fluid by an optical sensor, the method comprising: causing a fluid to enter into a gap of a gap-forming member, the gap located on an optical path from a light-emitting element to a light-receiving element; causing a light emitted by the light-emitting element to pass through the fluid; causing the light-receiving element to detect a color of the light that has passed through the fluid; calculating brightness of the detected color of the light; calculating a color component calculation value that is a value calculated based on a maximum value and a minimum value among an R value, a G value, and a B value of the detected color of the light; and determining a state of the fluid based on the calculated brightness and the calculated color component calculation value, wherein determining a state of the fluid based on the calculated brightness and the calculated color component calculation value comprises determining the deterioration state of the fluid by determining that the state of the fluid is a state predetermined with respect to a combination of the calculated brightness and the calculated color component calculation value.