Patent ID: 7545487

Claim:
A device for inspecting eggs for the presence of blood, comprising: a light source in order to pass light of a first wavelength which is not selectively absorbed by blood and light of a second wavelength which is selectively absorbed by blood through an egg to be inspected, detection means for converting the light transmission through the egg to be inspected for each of the two wavelengths into corresponding signals, each of the said signals being representative of the light transmission at the relevant wavelength, signal-processing means which are designed to determine the ratio between the light transmission associated with the first wavelength and the light transmission associated with the second wavelength based on the signals emanating from the detection means and to emit a decision signal which is representative of the decision whether or not an egg contains blood on the basis of this ratio, wherein the light source comprises one or more identical LED's (Light Emitting Diode) for generating the light which passes through the egg, wherein the one or more identical LED's in use emit light within a certain narrow spectrum, which spectrum comprises both the first and the second wavelength, wherein the signal-processing means is designed to detect a variation in the ratio between the light transmission associated with the first wavelength and the light transmission associated with the second wavelength during an inspection of a plurality of eggs in succession and to correct an effect of the variation in the ratio on the decision whether or not an egg contains blood.