Color Measuring head and Scanner Device Equipped Therewith

Scanner device for measuring the color properties of a measured object pixel by pixel, comprising:

• a color measuring head that is adapted to be moved in at least one dimension across a measurement object to be measured, the color measuring head including at least one illuminating channel and a collection channel, wherein the illuminating channel including a light source and optical means for illuminating the measured object at a measurement site at a mean angle of incidence of 45°, and wherein the collection channel includes optical means for capturing measurement light emitted from the measured object at the measurement site at a mean collection angle of 0° and coupling it into a light guide which directs the captured measurement light to a wavelength-selective photoelectric transformer, which is adapted to resolve the captured measurement light into a number of wavelength ranges and to generate an electric measurement signal corresponding to each wavelength range,
• wherein the optical means in the illuminating channel comprises collimation optics, a field aperture, symmetrical telecentric imaging optics and a polarization filter,
• wherein the optical means in the collection channel comprises imaging optics, a field aperture and coupling optics,
• wherein the collimation optics collimate the illuminating light emanating from the light source, thereby illuminating the field aperture of the illuminating channel essentially homogeneously axially parallel,
• wherein the polarization axis of the polarization filter is tilted so as to be oriented at an angle of 45° with respect to the plane of incidence onto the measured object,
• wherein the telecentric imaging optics are adapted to reproduce the field aperture sharply in a measurement plane, thereby creating an illuminating speckle,
• wherein the imaging optics in the collection channel reproduce the field aperture sharply in the measurement plane within the illuminating speckle and a measurement speckle is defined by the image of the field aperture, and
• wherein the collection channel is adapted to capture measurement light emanating only from the measurement speckle and to couple the captured measurement light via the coupling optics into the light guide.