from The Century Dictionary.
- In optics, having a wide and flat field of view: used as a tradename for certain achromatic combinations of lenses, as for photographic use, or for handmagnifiers.
Sorry, no etymologies found.
How she fastened these cross-pieces to the ray-lines I could never quite make out, though I often followed the work closely from inside through the pane of glass with a platyscopic lens; for, strange to say, the spiders were not in the least disturbed by being watched at their work, and never took the slightest notice of anything that went on at the other side of the window.
One year in Italy with their eyes open would be worth more than three at Oxford; and six months in the fields with a platyscopic lens would teach them strange things about the world around them that all the long terms at Harrow and Winchester have failed to discover to them.