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adrian_b a day ago

Approximately.

The Geissler tubes used for lighting, including those filled with neon, use the light of the so called "positive column" of gas, which emits light from almost the entire length of the tube, regardless of its form, which also allows to curve the tube, e.g. in the form of a letter.

The neon indicator bulbs use the so-called "negative light", which is emitted from a small region around the metallic cathode, while the rest of the volume of the bulb emits no light. Because the light-emitting zone is around the cathode, shaping the metallic cathode, e.g. in the form of a digit, will give the same form to the light.

When electric discharges are done in a tube with low-pressure gas, there may be various parts of the tube that emit light, depending on the pressure of the gas, on the applied voltage and on the dimensions and form of the tube and of the electrodes.

While the emitted light can also have other aspects, only 2 variants are used in practical applications, the positive column light for general lighting and the negative cathode light for indicator or display applications.