An attenuating optical shutter for high speed spectral analysis of an optical radiation band so as to derive N wavelength-dependent portions thereof. The attenuating optical shutter incorporates an optical shutter body including N shutter segments, each selectably switchable between a first substantially transparent and a second substantially opaque optical state, and a multi-zone attenuator comprising N optical attenuating zones each having a different predetermined wavelength-dependent attenuation characteristic. Each of the shutter segments is optically interconnected with a respective one of the N optical attenuating zones of the multi-zone attenuator thus forming N respective cells of the attenuating optical shutter. Such an attenuating optical shutter finds particular application in a spectrometer. A method for determining the spectral function of a sample using the attenuating optical shutter is also described.

A fast mechanical shutter, based on rotating chopper wheels, has been designed and implemented to shutter the entrance slit of a spectrograph. This device enables an exposure time of 9 .mu.s to be achieved for a 0.8 mm wide spectrograph entrance slit, achieves 100% transmission in the open state, and an essentially infinite extinction ratio. The device further incorporates chopper wheel position sensing electronics to permit the synchronous triggering of a laser source.

A multi-slit type spectrometer includes a light diffracter which diffracts an incident light according to wavelengths; an optical shutter array member including a plurality of optical shutter elements arranged in correspondence with wavelength bands diffracted by the light diffracter, operable to transmit an incident ray according to an applied voltage, and made of PLZT. A zone of a given number of adjacent optical shutter elements is applied with a voltage corresponding to the wavelength bands of the rays incident upon the zone of adjacent optical shutter elements at a specified timing so that the rays respectively pass through or are reflected at the optical shutter elements. A signal processor receives the ray which has passed through or has been reflected at each optical shutter element and outputs an electrical signal according to the intensity of the received ray. A calculator calculates the intensity of the incident ray for each wavelength band in accordance with the electrical signal output from the signal processor and the specified applying timing.

An intensity of light emitted from a lamp is passed through a mirror tunnel and is directed to a disk which comprises three, B, G, and R, color filters, each extending 120 degrees on the disk. Each of the B, G, and R modes of light, separated on the disk, is guided through the optical fiber bundle and is transmitted to the PLZT elements. A pattern of the PLZT elements, determined by a group of dots of exposure data to be printed, are energized by a given voltage in synchronization with the rotation of the disk 13, thus allowing a desired mode or wavelength of light to pass selectively and fall efficiently on the printing paper.

This spectral characteristic measuring apparatus measures two-dimensional spectral characteristics of a sample, and the apparatus includes a collimator lens, band-pass filters, lenses and an area sensor, which are arranged in order on an optical axis L. The collimator lens transforms light outputted from the sample into a pencil of parallel light. The band-pass filters have mutually-different passbands. The lenses have an identical focal distance and are arranged in correspondence with the band-pass filters. The area sensor is arranged at the focal points of the lenses and constructed of a number of imaging devices such as CCDs arranged two-dimensionally. As described above, the images spectrally separated by the band-pass filters are formed in mutually-different positions on the area sensor. Therefore, the two-dimensional spectral characteristics of the sample can be simultaneously measured with the simple construction.