Email from Lieven 2018-01-26 to tlhIngan Hol mailing list:

Anyone who has watched Discovery might have noticed that Lorca is sensitive to light. In another scene, Burnham said that the light is different where she is. These are two different things:

Marc Okrand wrote:

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For this, 'otlh "photon" would work, but even though it's scientifically correct (I think), it would be confusing in a Star Trek context because of photon torpedoes and such (and because there can be photons besides those in the visible light part of the electromagnetic spectrum).  You're right — Klingons would have a word (at least a scientific, technical term) for the phenomenon of light (aside from 'otlh).

wovtaHghach is one such word. Another is tamghay "light, luminescence, illumination" ("illumination" here does not mean "clarification, explanation, explication" or the like).

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Okrand later added:

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You're right. They are different (and, like you, I'd use tamghay for the examples you sent), but one's eyes could be sensitive to wovtaHghach.  For "the light is different," however, wovtaHghach isn't so good (unless they're talking about the intensity of the brightness or something like that as opposed to, say, the color).

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So when saying that Lorca is sensitive to "light", it's actually the wovtaHghach bothering him. Otherwise, he would have to live in absolute darkness, where there is no tamghay.

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tamghay Hurgh sounds odd to me for some reason. I think it would be tamghay wovHa', which perhaps could be translated as "dim light."

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