Abstract: A stage lighting instrument having a high-intensity light source or lamp coupled with a concave reflector, and a projection optical system having a lens system that includes a well-defined aperture stop. The lens system forms a real image of the light source near the aperture stop. A color filter and dimming system may be located within the lens system so that the color filter and dimming elements occupy a volume of space near the aperture stop and within the real image of the light source. By locating the color and dimming apparatus near the aperture stop and within the volume occupied by a real image of the light source, superior color mixing, dimming and integration is achieved using simple, unpatterned filters and a simply-shaped dimmer panel. A color filter and dimming system may alternatively be located as close to the light source as possible so that a real image of the color filter and dimming elements is formed near the aperture stop where the image of the light source is formed.

Abstract: A light beam shutter apparatus for a lighting instrument includes several individual shutter mechanisms arranged radially around the axis of a light beam. Each shutter mechanism includes a generally circular shutter blade having a circumference, but with a cut-out or void area such that a portion of the circumference is eliminated. The shutter blade preferably includes at least one straight edge at the boundary of the cut-out or void area, which straight edge passes through the center around which the shutter blade rotates, and is used for intercepting at least a portion of a light beam passing through the light beam shutter apparatus. The shutter blade may alternatively include other edge shapes at the boundary of the cut-out or void area, as desired. Driven surfaces, such as gear teeth or the like, are formed in opposed portions of the remaining circumference.

Abstract: A zoomable light beam spreader comprising first and second multiple-lens arrays includes a plurality of plano-convex lenses in correspondence with a plurality of plano-concave lenses having matched, curved optical surfaces. In a zero-power state, the two multiple-lens arrays are very closely spaced so that the matched convex and concave surfaces effectively cancel each other optically but, as the two arrays are separated coaxially along the axis of a light beam, beam divergence angle increases as a function of the distance of separation. A large amount of beam divergence is obtained when the curved surfaces of the plano-concave lenses of the second array are positioned beyond the focus points of the plano-convex lenses of the first array.

Abstract: A deconcentrating optic has an input aperture positioned near a point of minimum focus of a reflector, and has an output aperture which is larger than the input aperture. An inner surface connects the two apertures of the optic. The surface is reflective to visible light, and is shaped to decrease the angles of incident light rays from the reflector so that an emerging light beam is bounded by a cone the angle of which is less than or equal to the acceptance cone of a projection lens. The size and shape of the output beam is such that the object lying in the projection plane of the lens is fully illuminated but not overfilled. The inner surface of the reflecting optic may be selectively perturbed so that the object plane of the projection lens is uniformly illuminated. The general shape of the reflecting optic's inner surface may be parabolic, elliptical, hyperbolic, circular, conical, or combinations of these shapes.

Abstract: Architectural luminaries utilize a common optical engine having a lamp coupled to an ellipsoidal reflector, a field stop aperture, and image-projecting lenses A color wheel, gobo wheel, and mechanical dimmer may also be included. A microlens element converts a spotlight optical engine into a wash light optical system. A multiple lens array provides variable diffusion. The optical engine is combined with an X-Y scanning mirror beam direction system in a substantially recessed housing for mounting in the ceiling of a building. The optical engine is combined with a pan-and-tilt yoke for greater range of coverage with an exposed luminaire.

Abstract: A projection zoom lens system is used in imaging and non-imaging modes for entertanment and architectural illumination, providing 8:1 zoom ratio in an imaging mode and 20:1 zoom ratio in a non-imaging mode. When coupled with a variable aperture iris, beam size control is obtained with 120:1 ratio. The lens system comprises four lens groups: a first group having a positive refractive power, a second group having a negative refractive power, a third group having a negative refractive power, and a fourth group having a positive refractive power. In the imaging mode, the third group is adjusted axially to vary magnification while the second group is adjusted axially to focus on the object. In the non-imaging mode, the second and third groups are brought into close proximity with each other and adjusted axially as a unit to vary magnification. The fourth group remains fixed and the first group can be adjusted axially to focus the image at different throw lengths.

Abstract: A switch-mode power converter uses a digital signal processor (DSP) to control operation of power semiconductors through gate drive amplifiers, further using the DSP's internal analog-to-digital converters to measure necessary currents, voltages and timings within the main power circuit. Using values captured by the A-to-D converters, software controlling the DSP manipulates duty cycle and timing parameters of the main semiconductor switches to provide at least three different modes of operation for serving a wide range of lighting loads. This power system reduces the size, cost, and weight, of circuitry needed to operate stage lighting equipment. The DSP's microprocessor eliminates most of the complex and dedicated analog circuitry commonly used for electronic power conversion, and a common power circuit topology provides an identical hardware platform for each luminaire circuit. Overall reliability is enhanced because of the reduction in circuit complexity.

Abstract: A high intensity light projector for stage, architectural and similar applications includes a controllable image quality projection gate providing advanced visual effects. The projection gate, capable of selectively scattering or transmitting incident light, may be constructed of an array of scattering liquid crystal material in combination with infrared and ultraviolet reduction means which provide in the high intensity beam, a stable thermal environment by minimizing the absorption of light by the projection gate. Additional thermal efficiency is provided by supplemental cooling means. Color control is also provided in the form of dichroic filter wheels forming cooperating adjustable low, high and band width filters including saturation control. A color measuring feedback sensor is also provided. An intensity measuring feedback sensor controls a spatially-modulated, variable-density, reflectively-coated dimming wheel. A programmable gobo system has provisions for gobo selection, orientation, and rotation.

Abstract: A color filter plate includes a continuously-variable dichroic filter coating constituting a variable band-pass or variable band-reject filter having a spatially-modulated variable-density pattern formed in the coating, and provides continuously-variable hue and saturation characteristics along separate gradient axes. A color filter mechanism includes a sequential arrangement of rectangular or circular color filters, having continuously-variable band-pass or band-reject filter coatings, mounted in motorized carriages. One mechanism provides two-axis translation of the rectangular color filters while another mechanism provides translation and rotation of the circular color filters. A light projection system comprising a lamp with a reflector and a lens includes a color filter mechanism having sequential, continuously-variable band-pass and band-reject filters supported by motorized carriages mounted in a region where the beam diameter is small.

Abstract: A light pattern generator includes a reflective layer absorptive to infra-red radiation from which a desired pattern has been removed to allow passage of a light beam in the shape of the pattern. A method for making a light pattern generator includes forming a layer of reflective material on a transparent substrate and ablating a portion of the layer with a laser to create a desired pattern.

Abstract: An optical system for an image projector luminaire includes a variable-focus lens having a depth-of-field adjustable as to location along an optical axis, and two carriages each supporting at least one image pattern generator at separate locations along the optical axis, at least one of those carriages being adjustable as to location along the optical axis. The system is operable to bring either or both image pattern generators into focus. Each carriage may support pattern generator exchanger mechanisms for selecting one of a plurality of available patterns, and may also rotate the selected pattern. The movable carriage, the lens, and the pattern exchanger mechanisms may all be motorized and operable by remote or computer control.