- n transmission and reproduction of photographs and charts and pictures over a distance
- n photography using a telephoto lens
- Four years ago he invented vacuum bulbs used in telephotography (sending still pictures by electricity or radio); three years ago he improved the bulb so that it would transmit .
- Alexanderson's feat was to utilize a beam of light (which in motionless telephotography has from 2 to 20 minutes to trace and transmit the desired light-pattern or image) at .
- The device is somewhat similar to that used in " telephotography," the light reflected from the pictures being cut into innumerable flashes by a " radio eye," a revolving disc .