From that one photo, I'm not really seeing anything to worry about on that leaf. I grow a number of Phals, in fact, that's the only type of orchid I grow right now. Occasionally, there will be a plant that just looks perfect in every way, but more often, each plant will have its own little eccentricities. A crooked leaf here, a scar or mechanical damage there, a leaf or part of a leaf that is not of a perfectly uniform color or texture.
Keep an eye on it, of course, and if it gets worse or seems to spread, let us know.