Selected unworked slab of calculated lower density
Selected unworked slab of calculated lower density, free from infections, stage in the manufacture of 'Kryptok' bi-focal spectacle lenses.
Details
- Category:
- Optics
- Object Number:
- 1921-323/54
- Measurements:
-
overall: 50 x 50 mm
- type:
- ophthalmic lens
- credit:
- Dunscombe collection of spectacles
