An optical device capable of detecting the intensity and wavelength of light from a light source with a high level of precision, and an optical module incorporating the optical device. An image sensor records an image from a print substrate, which is imprinted with ink, inside the printing unit, and sends data correlated to that image to an evaluation unit. The object is introspect so available data and methods information can be used to populate a corresponding object interaction description and present an object interaction session. The crushing chamber is provided with a slot-formed discharge opening which may be varied in width.