Abstract:
An adjustable slit plate assembly for a monochromator is formed by two identical metal plates (P1, P2) each having a set of slits (EX1 to EX6 and EN1 to EX6 respectively) with all the slits disposed on a common circle. The plates (P1, P2) are located and supported on a disc (SM) on a rotatable shaft (SH) at the axis (A) of the circle. The slits are each of minimum length to pass a radiant beam of given energy through the monochromator and each set of slits occupies an arc of substantially minimum length. The shape of each plate is substantially a sector of a further circle whose radius and arc are the minimum necessary to accommodate the slits and the axis. The complete configuration of the plates is formed by etching in a single operation, and a greater number of slit sets can be formed together from a plate of given area than for the prior art case in which the two sets of slits for a slit assembly are formed in a single plate in the shape of a complete disc. A significant cost reduction in the slit assembly is thus achieved.
Abstract:
An apparatus for measuring a diamond color comprises a light source composed of a lamp and an integrating sphere for diffusing light therein emitted from the lamp; a diamond holder including diamond supporting head means and suction base means, thereby positioning the table facet of the diamond in the integrating sphere for allowing the diffused light from the light source to fall on the table facet of the diamond; a monochromator for separating a beam of light as it emerges from the diamond through the table facet side into a spectrum; a photodetector for detecting the light from the monochromator; variable slit means disposed in at least one of the monochromator and the photodetector for adjusting the size of the beam of light to a diameter of the diamond; a measurement unit for controlling at least the monochromator to obtain a spectrum of the light which has passed through the diamond; and an arithmetic unit for deriving tristimulus values X, Y and Z from the spectrum of the light from the diamond; which is able to measure the colors of brilliant-cut diamonds easily and objectively.
Abstract:
A dispersive optical spectrometer is disclosed which comprises light detection means, dispersion means for separating light radiation into spectral components and for directing the spectral components toward the light detection means, means for admitting light radiation into the entrance focal plane and for directing the light radiation toward the dispersion means, the light radiation admitting means including a plurality of spaced-apart apertures, and light transmission means for transmitting light radiation from a light source to one or more of the apertures.
Abstract:
The slit assembly of the present spectrometer comprises a liquid crystal cell. The electrodes of the cell are selectively actuated for producing a pattern of slits appropriate to the spectral lines of interest in the spectrum derived from the substance under analysis.
Abstract:
Apparatus for controlling the width of an adjustable slit in response to the product of two variable functions, one of which is programmed, which includes at least one adjustable optical slit; slit width programming apparatus for producing a first displacement that is a logarithmic function of the instantaneous slit width conforming to a predetermined program; antilogarithm generating elements for producing a second displacement that is the antilogarithm of the first displacement; a phase adjusting mechanism for controlling the phasing between the first displacement and the second displacement; slit width selection apparatus operative on the phase adjusting mechanism for controlling the phasing in accordance with a given slit width selection; and actuating elements responsive to the second displacement and operative on the optical slit for controlling its width.
Abstract:
The present invention is to provide a double-pass type double monochromator having a high resolving power and an improved relative speed. To this end, there is provided an improved optical system in which the number of times light passes through the light dispersing element is doubled only with the provision of inexpensive reflector elements.
Abstract:
There is disclosed a flexible mounting structure, rigidly supported at only two locations, for providing opposed precision motion of at least two mounting surfaces oppositely disposed upon the mounting structure in response to a force coupled symmetrically applied to the mounting structure. A pair of resilient connecting members, each having one of the two locations for support, and a pair of rigid mounting rails, each rail having at least one of the mounting surfaces disposed thereon, are connected to form a parallelogram whereby the mounting surfaces are substantially parallel. A rotatable shaft is disposed at right angles and adjacent to the rigid mounting rails. A drive tape is connected between the rotatable shaft and each of the rigid mounting rails in such a manner that as the shaft is rotated, each drive tape wraps around the shaft to provide the symmetrical force couple which moves the mounting rails. A cam follower arm is attached to the rotatable shaft and a cam roller bearing attached to the arm rides on a rotatable cam. Optical elements attached to the mounting surfaces transverse a precision path in accordance with the motion of the mounting rails.