GB806896A - Improvements in or relating to apparatus for displaying the properties of light - Google Patents

Abstract

806,896. Educational appliances. GRIFFIN & GEORGE Ltd., and MORRIS R. H. April 12. 1957 [April 12. 1956], No. 11215/56. Class 146(2) An apparatus for displaying the properties of light comprises a light box 28 which has means for supporting a light source therein, an opening at one side, and wing portions 33 extending from the opening substantially in line wth the sides of the box and each having a number of locating means spaced apart along its length for accommodating a number of elements which modify the light rays from the source. The box, which may be moulded from metal or plastics, is open at the bottom, and has on apertured front wall 32, and the side walls 29 and wings 33 have sharp edged horizontal heat radiating ribs 34.. Ribs 35, 36. 37 on the wings 33 form guideways for holding equipment such as a shutter 48 slotted to produce one or more parallel beams, lens 53, and a centrally apertured stop plate 54. The lamp has a straight vertical filament 43 and is adjustable lengthwise of the box, being then secured by a clamping ring 40. The base board 10 standing on rubber feet 11 has a turntable 21 rotatable thereon on which a reflecting mirror &c. may be mounted. e.g., by clips, the turntable bears a scale 24, and the board and turntable are matt white. The box is secured to the base 10 by split pegs 44. Fig. 19 shows a multiple part adjustable mirror, mirror part 62 being fixed and mirror parts 63, 64 being adjustable about pivots 69, 70 by means of screws 78 and urged towards the position shown in Fig. 19 by springs 71, 72. This mirror may be positioned by engagement of a projection 89 on inclined bifurcated portions 81, 82 in groove 83 or 84, and if a shutter with three slots is arranged between ribs 37 and the box, and a screen with three vertical transparent coloured strips, e.g., red, green and blue, 63, arranged between ribs 36, the mirrors 62, 64 may be used to combine differently coloured lights. The box may be arranged further from the turntable by means of an extension piece which may be attached to the bas 10 and has split pegs for securing the box. The side and back walls are recessed at 42 to permit ventilating air to enter the box.