abstract |
A conical illuminator for use in colorimetry, spectrophotometry, densitometry or sensitometry. In a preferred embodiment, light from a source such as a pulsed xenon lamp is integrated within an integrating chamber. The light source may be placed in a second integrating chamber adjacent to the aforementioned integrating chamber. Alternatively, the lamp may be placed directly within the integrating chamber. The light is emitted through an exit port and conformed to a conical configuration, according to a pre-selected standard, via an annular stop. An imaging optic relays the conformed light uniformly onto a sample plane. The annular stop is placed at or near the tangential focal length of the imaging optic. The annular stop may be coated with a light absorbing coating, or can be formed with a grooved or mirrored surface. Alternatively, in lieu of an integrating chamber, a diffuser may be employed for homogenizing the light. Various configurations of the imaging optic and annular stop are possible. |