polarization photometer
Datecirca 1930
Inventory Number1996-1-0719
ClassificationPhotometer
Subject
Maker
Bausch & Lomb Optical Company
1853-present
Cultural Region
Place of Origin
Dimensions14.5 × 17.3 × 26.5 cm (5 11/16 × 6 13/16 × 10 7/16 in.)
box: 17.8 × 28.6 × 19.7 cm (7 × 11 1/4 × 7 3/4 in.)
box: 17.8 × 28.6 × 19.7 cm (7 × 11 1/4 × 7 3/4 in.)
Material
Bibliography
DescriptionThe optical system of this photometer consists of a polarizer (Wollaston prism), an analyzer (Glan-Thompson prism), rhomboid prisms (though which light first comes in the instrument), collective lenses, a bi-prism collective lens, an eyepoint diaphragm, a graduated scale and a loupe or scale reader. One quadrant of the scale is graduated in densities, a second in transmission (in percent), and the third and fourth in degrees. It is made of German silver. This instrument was usually mounted on a stand or optical bench.
Signedon plate: BAUSCH & LOMB OPTICAL CO / ROCHESTER, N.Y. U.S.A / No. 685.
FunctionFor comparison of light intensities. According to a 1929 B&L catalogue: "The instrument is designed with two ends in view. (1) When used in conjunction with the standard light source it is an excellent white light photometer and will serve for accurate measurement of light intensity. When used alone in connection with an extended uniform source it offers means for the measurement of photographic densities and work of a like nature.
(2) When used with a No. 2700 Spectrometer and the No. 2750 Universal Stand, it provides a complete Spectrophotometric outfit of a high order of accuracy. It will then give over the visual range readings from whcih spectral transmission and density curves may be directly plotted."
(2) When used with a No. 2700 Spectrometer and the No. 2750 Universal Stand, it provides a complete Spectrophotometric outfit of a high order of accuracy. It will then give over the visual range readings from whcih spectral transmission and density curves may be directly plotted."
R. & J. Beck
Date: 1876
Accessories: Beck patent substage condenser (1122c); apertometer (1122d)
Object number: 1122b
Ferdinand Ernecke
Date: 1880-1910
Accessories: wooden base
Object number: 2020b
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
Jean Baptiste François Soleil
Date: 1840-1850
Object number: 1998-1-1227