You can produce different brilliant colors on titanium, or on metal coated with a titanium sputtered coating, by producing different thicknesses of titanium dioxide surface layers. Because titanium dioxide has such a high refractive index — 2.5–2.6 — the reflection from the top of the coating is much stronger than from other similar metal oxide coatings, resulting in almost complete interference and thus strongly saturated iridescent colors.
The conventional way of making such oxide layers on titanium is by heating it in air, with the temperature of the surface largely determining the thickness of the oxide, but this carries the drawback that it can generally only produce very gradual variations of thickness across a surface, because if there are large temperature differences over small distances in the surface, they will quickly disappear. Perhaps with localized laser heating, this disadvantage could be removed.
But I have another idea in mind. Rather than heating the material to promote diffusion of oxygen through the oxide layer, let’s anodize it. This involves applying a positive voltage to the titanium in an aqueous electrolyte, stealing electrons from the surface metal atoms and giving them to water molecules, liberating oxygen from them to combine with the metal.
Anodizing titanium to produce different colors is a known technique: https://thekidshouldseethis.com/post/anodizing-titanium-the-rainbow-metal, for example.
If this is done with a cathode very close to the surface of the anode, it should produce a very localized coating; and applying varying amounts of current to different spots on the anode should produce different coating thicknesses, and thus different colors.
This should enable the production of brilliantly colored patterns on titanium surfaces. I don’t know if the full gamut of visible colors can be thus produced by dithering light from nearby dots, but I suspect so.