Denisyuk's 1962 reflection hologram lacked a laser to prove itself

What you see

Dennis Gabor's own account of this work, given in his 1971 Nobel lecture, "Holography, 1948-1971," describes the intended result: a viewer illuminating the developed plate with a point source similar to the original reference beam should see the recorded object reappear "in the original position and (unless the emulsion has shrunk) in the original colour," without needing to look through the plate as a transmission hologram requires. But Gabor is explicit that Yuri Denisyuk's actual 1962 result, made without a laser, was only a proof of principle, not a robust object a visitor could reliably view.

How it works

Gabor's lecture lays out the geometry: unlike Leith and Upatnieks' arrangement, where object and reference beams enter the emulsion from the same side, Denisyuk's "important paper" of 1962 has the two beams fall on the emulsion from opposite sides. The resulting standing waves form layers of developed silver that, instead of running parallel to the surface as in Gabriel Lippmann's earlier colour photography, bisect the angle between the two beams. Illuminating that layered structure with a matching reference wave later reflects an image back at the viewer, combining Lippmann's colour-interference layering with a recorded three-dimensional scene rather than a flat colour photograph. Gabor cites the paper by its full title and journal record: Denisyuk, Yu. N., "Photographic Reconstruction of the Optical Properties of an Object in its Own Scattered Radiation," Doklady Akademii Nauk SSSR, 144, 1275-1278 (1962).

Viewing conditions and limits

The Bragg-selective layering this geometry produces is, in principle, exactly what allows white-light reconstruction, since the structure diffracts strongly only near the original recording wavelength and angle. But Gabor states plainly that "lacking a laser in 1962 he could produce only an 'existence proof,'" and that the first two-colour reflection hologram that could actually be reconstructed under white light was made three years later, in 1965, by G. W. Stroke and A. Labeyrie, not by Denisyuk himself at the time of his original paper.

What it is not

This is not the Leith-Upatnieks transmission method, which records both beams from the same side and reconstructs only under laser light; and per a Nobel laureate who tracked the field closely, it should not be read as a fully solved, shippable white-light hologram achieved in 1962. It was a theoretical and experimental proof of concept awaiting a light source that did not yet exist for Denisyuk to use.

• Is Denisyuk credited with proposing the single-beam reflection geometry, or with fully demonstrating a white-light hologram in 1962?
• Does an account naming a "first white-light hologram" cite Denisyuk's 1962 paper or Stroke and Labeyrie's 1965 result?
• Is the original Russian-language publication cited directly, or only through a later secondary account?

Denisyuk's own original paper is thin on the ground in English-language sources; what survives clearly is a contemporary expert's account, from a physicist who was tracking the field as it happened and had every reason to get the credit right. That account draws the line precisely where a careful reader needs it: between the idea and its later, fuller demonstration.