Hartl optical disk
Date1930-1950
Inventory Number1997-1-0014
ClassificationOptical Demonstration Apparatus
Subject
Maker
Central Scientific Company
1889 - 2000
Cultural Region
Place of Origin
Dimensions45.2 × 40.3 × 26 cm (17 13/16 × 15 7/8 × 10 1/4 in.)
Material
Bibliography
DescriptionThe aluminum disk can rotate and is supported by a heavy tripod. It is partially shielded by a metallic hood, in which a series of slits have been cut-out to allow rays of light to pass through and fall on the optical accessories attached to the disk. Color filters can also cover the slits. The disk itself is graduated in single degrees in four quadrants of 90 degrees each, numbered in tens. On it are outlined shapes of optical accessories (prisms, plates, lenses, mirrors, etc.) on which light falls. They are there so that light coming through the slits strikes the accessories at correct angles. These accessories are missing.
Signedon disk: CENTRAL SCIENTIFIC CO.
on disk: CENCO
Inscribedon disk: HARTL OPTICAL DISK
on disk: SOLE AUTHORIZED MANUFACTURERS
FunctionThis is how one of Cenco's trade catalogues describes this instrument: "A complete laboratory in optics, designed to illustrate in a simple and perfect way the fundamental laws of optics. An intense beam of parallel rays is necessary, for which sunlight may be utilized either directly as it falls into the room through a partly shaded window or is reflected by means of a simple mirror. It is not necessary or desirable to use a darkened room. When direct sunlight is not available, No. 85261 Cenco Arc Illuminator is the m most satisfactory source of artificial light. The paths of light rays upon the 30 cm graduated aluminum disk and through the lenses and mirrors can be seen by the entire class.
The graduations to single degrees and the numbers are easily observed. The Hartl design permits the use of the optical disk in either vertical or horizontal position. A great variety of optical experiments may be performed with this apparatus. These experiments with a single ray or several parallel rays include the following: 1. Angle of reflection. 2. Angle of refraction. 3. Index of refraction. 4. Total reflection. [...] 10. Stereo binocular. 11. Refraction through a parallel plate. [...] 15. Dispersion showing spectrum. 16. Theory of the rainbow, formation of primary and secondary bow."
The graduations to single degrees and the numbers are easily observed. The Hartl design permits the use of the optical disk in either vertical or horizontal position. A great variety of optical experiments may be performed with this apparatus. These experiments with a single ray or several parallel rays include the following: 1. Angle of reflection. 2. Angle of refraction. 3. Index of refraction. 4. Total reflection. [...] 10. Stereo binocular. 11. Refraction through a parallel plate. [...] 15. Dispersion showing spectrum. 16. Theory of the rainbow, formation of primary and secondary bow."
Jules Duboscq & Philibért François Pellin
Date: 1885-1900
Object number: 1997-1-1481
Heinrich Daniel Ruhmkorff
Date: 1860-1875
Object number: 2006-1-0013
Ernst Leitz (company)
Date: circa 1919
Accessories: oculars (2): 3, 8x; accessory box; Leitz objectives (5); wrenches (2); ground glass; N.A. 1.45 condensor cap; Abbe condensor; rotary stage; case
Object number: 1345
Eimer & Amend
Date: circa 1922
Accessories: set-up instructions; weights; corked glass viles; tweezer; magnifying glass
Object number: 1996-1-0207
Ernst Leitz (company)
Date: circa 1937
Accessories: standard eyepieces (3): 8X P, Periplan. OK 10X, and Periplan. Ok. 25X; wide eyepieces (3): 1, 1, 8X, 10X; objectives (4) in fitted case: 1b 4.3X, 3 10X, P7 62X, P 1/12 oel; waveplates (2); condenser with polarizer; mechanical stage; loupe 6x; box of cover glasses; standing case; key; objective adaptors (4); and watch keys (2)
Object number: 1999-1-0020a
Central Scientific Company
Date: 1935-1950
Accessories: instruction manual
Object number: 1997-1-0358a
