Spectrometry device, image forming apparatus, and spectrometry method

A spectrometry device comprising:

• a spectroscope that includes a wavelength-selective interference filter on which light from a measurement target is incident, wherein the spectroscope is configured perform spectrometry on the measurement target;
• and
• a moving mechanism that moves the spectroscope relative to the measurement target in one direction, wherein:
• when the measurement target is a color patch, the spectroscope changes a wavelength of light passed by the wavelength-selective interference filter in a first period during which the spectroscope is relatively moved in the one direction, the wavelength-selective interference filter passes light of a first wavelength at a start of measurement and at an end of measurement in the first period, and a first measured value that is a measured value from the spectrometry at the start of measurement is compared with a second measured value that is a measured value from the spectrometry at the end of measurement.

A spectrometry method comprising:

• providing a spectroscope that is configured to move relative to a measurement target;
• measuring a first measured value of light at a first wavelength at a first time using the spectroscope;
• measuring a second measured value of light at a second wavelength at a second time using the spectroscope;
• measuring a third measured value of light at the first wavelength at a third time using the spectroscope;
• and
• comparing the first measured value with the third measured value.

A spectrometry method that performs spectrometry on a color patch as a measurement target by using a spectrometry device that includes a spectroscope, the spectroscope includes a wavelength-selective interference filter on which light from the measurement target is incident and a moving mechanism that moves the spectroscope relative to the measurement target in one direction, the method comprising:

• relatively moving the spectroscope in the one direction;
• performing spectrometry by changing a wavelength of light passing through the wavelength-selective interference filter in a first period during which the spectroscope is relatively moved;
• passing light of a first wavelength through the wavelength-selective interference filter at a start of measurement and at an end of measurement in the first period;
• and
• comparing a first measured value that is a measured value from the spectrometry at the start of measurement with a second measured value that is a measured value from the spectrometry at the end of measurement.