Monoyer vintage ophthalmologist's light scale of visual acuity

Metal body supporting a screen-printed plexiglass plate of letters and numbers that make up the scale of visual acuity. It is covered by a glass plate. It is electrified and has a double switch. Very nice deco idea, trendy object, playful atmosphere lighting. Very good general condition. Dimensions: height 77.5 cm - width 27 cm - depth 12 cm. For the record: how many patients, under the baton of their therapist, have mobilized all their efforts and their concentration to scrutinize him in every detail, without knowing that he contained a hidden secret. In france, this panel hides a double inverted acrostiche. By taking the first letter of each line from the bottom, you get m-o-n-o-y-e-r-d-m, which gives monoyer dm. And by taking the last letter from each line, we get ferdinand. Ferdinand monoyer, doctor of medicine, is the inventor of the test that bears his name and signature. Very good condition and in working order.