Patent ID: 7645010

Claim:
An ink ejection amount measurement method for an inkjet recording head, the ink ejection amount measurement method comprising: an ink ejection step of ejecting ink onto a recording medium from a recording head by applying a drive voltage to the recording head, in such a manner that an ink dot image is formed on the recording medium; an image reading step of reading the ink dot image formed on the recording medium by means of an image reading device; a number of pixels measurement step of measuring number of pixels occupied by the ink dot image formed on the recording medium; a correlation table preparation step of preparing a correlation table representing a correlation among a value of the drive voltage, number of pixels occupied by an ink dot image formed on the recording medium, and an ink ejection amount ejected by the recording head; a drive voltage sweeping step of changing a value of the drive voltage applied to the recording head, from a first drive voltage measurement value which is a value of the drive voltage when the number of pixels measured in the number of pixels measurement step is a first number of pixels, to a second drive voltage measurement value which is a value of the drive voltage at a boundary where the number of pixels measured in the number of pixels measurement step changes from the first number of pixels to a second number of pixels; and an ink ejection amount calculation step of calculating the ink ejection amount when a drive voltage having the first drive voltage measurement value is applied to the recording head, according to the correlation table, using the first drive voltage measurement value and the second drive voltage measurement value.