REFLECTING OBJECTIVE AND CONDENSER
Stock Number: 10081
$950 the pair
For sale, Zeiss made two reflecting optics designed somewhat like a miniature Cassegrain telescope with one large concave mirror with central hole, and one small convex mirror with three-armed spider mount. In fact it is apparently the Schwarzschild system, developed in 1905.
2" (5 cm)
c. mid-20th century
Country of manufacture
REFLECTING OBJECTIVE AND CONDENSER, German, c. mid-20th century, the objective signed “Carl Zeiss, Jena, Spiegelobjecktiv, 40/0.65, 160/0.17, #014782,” the condenser “Carl Zeiss, Jena, Spiegelkondensor, 0.6, #209551.” Each is approximately 2″ (5 cm) tall, constructed of substantial plated metals, designed somewhat like a miniature Cassegrain telescope with one large concave mirror with central hole, and one small convex mirror with three-armed spider mount. In fact it is apparently the Schwarzschild system, developed in 1905. Condition seems excellent. One comes with a (non-original) case.
Unlike refracting optics, with glass and / or crystal elements, these reflecting optics offer chromatic correction over a wide spectral range from the deep ultra violet to the far infrared. Very expensive to produce, they offer possibilities unachievable with refracting lenses, and are an important step in the evolution of microscope optics.
Ask the Dealer
David and Yola Coffeen both have enjoyed academic careers, as planetary astronomer and as linguist/educator. But since 1982 (yes, 1982!) they have been full-time dealers in early scientific and medical instruments, under the name Tesseract. Selling primarily by catalogue (over 100 issued so far) they also have a web presence at www.etesseract.com, and can be contacted at email@example.com.