Origin of object glass
First recorded in 1655–65
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for object glass
The distance between the object-glass and the eye-piece of a telescope.
It is usually estimated by the clear diameter of the object-glass.
"This is the object-glass of our telescope," was the answer.
In the case of the object-glass of a telescope the image was at what we may call the short focus.
The front end of the telescope is open, there being no object-glass.
- optics another name for objective (def. 11)