Visual recording methods include electrolytic, carbon, hot air, ink and ink vapor, and wax.
Early workers made use of visual recording methods. For example, Greenwood in 1851 suggested ink recording; Carbonelle in 1906 designde a receiver for carbon paper recording of pictures; Bain in 1843 was the first to employ electrolytic methods for recording facsimile.
The following citations cover the modern version in the thirties of visual recording methods fairly well.
Delany (U.S. Patent 316, 754, P.B. Delany)
Ranger & Morehouse (U.S.Patent 1,819,264, R.H Ranger and F.G. Morehouse)
Ranger (U.S. Patent 1,770,493,U.S. Patent 1,819,197, U.S. Patent 1,841,452; I.R.E. Proc. Vol. 17, No. 6, June, 1929; R.H. Ranger)
Morehouse (U.S. Patent 1,779,261, U.S. Patent 1,850,600, F.G. Morehouse)
Bicknell & Ranger (U.S. Patent 1,844,199, R.S. Bicknell and R.H. Ranger)
Ludenia (U.S. Patent 1,875,063, W. Ludenia)
Young (U.S. Patent 1,848,862, C.J. Young)
Carlisle (U.S. Patent 1,958,885, R.W. Carlisle)
Fulton (Br. Patent 318,120,; Radio Craft, Vol. 6, pp. 718-743, June, 1935, Otho Fulton)
Siemes-Halske (Br. Patent 427, 257, Siemens, Halske)
Kleinschmidt (U.S. Patent 2,046,328, E.E. Kleinschmidt)
Elsey (U.S. Patent 2,063,992, H.M. Elsey)
Hogan (U.S. Patent 2,111,776, J.V.L. Hogan)
Schroter (U.S. Patent 1,882,043, F.Schroter)
(C) Marius Rensen