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Less interested in a smartphone that can project, and more interested in advances in glass and lenses that make smartphone cameras better.
In my experience, the battery life in most phones is fairly disappointing at the moment. I imagine that this would be a major hindrance to the usefulness of a projector. The increase in efficiency that this lens provides is great news but actual power consumption would be a more useful figure than a percent improvement. How much power will a small projector consume compared to a typical LCD screen?

Personally I would be much more excited to see LCDs with reflective modes rather than projectors. These would alleviate battery issues, solve the problem of screen clarity in direct light, and also ease eye strain. I'm keeping my fingers crossed :-).

This has very little to do with projectors in smartphones (or anywhere else), and what the article says about projectors in smartphones is mostly wrong.

Look at the title of the Alps press release. "Alps Develops and Commences Mass Production of [...] Lens for Optical Communication Using Wide-Angle Laser Diodes". Optical communication. This thing is meant to be attached to a laser diode and a length of optical fibre, not built into a projector.

Yes, they do make a throwaway remark that "the lens is also ideal for high-brightness projector applications". Whether that's true depends on whether it happens to be the exact aspherical lens that a given high-brightness projector application requires. Maybe it will be for someone. I wouldn't bet on it.

The coupling-efficiency figures cited by the article (taken from the Alps press release) would not be the relevant figures for a projector application. Alps do not appear to have provided any figures relevant for a projector application. One obvious reason for that would be that they're just talking about projectors as a throwaway remark and don't have any particular application in mind.

So far as I know, no palm-sized projectors use Peltier coolers. In fact, I'm not sure that any projectors use Peltier coolers. The Alps press release talks about Peltier coolers, but only in the context of optical communications. In any case, it seems unlikely to me that an improvement in efficiency from 0.73 to 0.68 is, in itself, going to make much difference to whether any given application requires cooling hardware.

The article suggests that a smartphone device might be able to project a 60" image. Making very optimistic assumptions at every point, I think that would call for at least 9W of power consumption even if you're happy for the image not to be very bright. This is not going to happen in a smartphone, no way, no how. (And that's ignoring the very substantial laser safety issues.)

The article suggests that even if this lens doesn't make super-bright smartphone projectors feasible, it might be useful for slightly larger projectors. Well, anything's possible, but the whole point of this lens is that it's extremely small, and for any projector that doesn't have to be squeezed into the tiniest space possible (and even for those that do) the difference between one of these lenses and a slightly larger one is unlikely to be significant.

(Disclaimer: My employer makes small video projectors that use laser diodes. I am not, in any way at all, speaking for them.)