1.   Even optical instruments, such as perspective machines, the cameraobscura and the camera lucida, were used sparingly.

2.   The first questions Wien asked were related to the resolving power of optical instruments.

3.   There is, however, one classical restriction which we must take into account, namely the resolving power of optical instruments.

4.   The company manufactures microscopes, telescopes, and other optical instruments.

5.   This level of magnification shows the eye as an optical instrument.

6.   But Sanders engineers are also packing the tiny platform with cameras and other optical instruments to feed data via radio to controllers on the ground.

7.   Dresden was historically a center for electrical engineering and the manufacture of optical instruments.

8.   Essilor, which makes products ranging from optical measuring instruments to contact lenses, believes the acquisition of Omega can help it to beef-up its U.S. operations.

9.   Flakes of paint could contaminate optical instruments on the Hubble.