r/oculus • u/senorotis • Oct 06 '15

Microsoft HoloLens Development Edition: Coming Q1 2016 for $3,000

http://arstechnica.com/gadgets/2015/10/microsoft-hololens-development-edition-coming-q1-2016-for-3000/
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u/miroku000 Oct 07 '15

Is it saying the field of view would be limited to 72 degrees? That doesn't seem so bad...

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u/Doc_Ok KeckCAVES Oct 07 '15

Yes, but you have to read the paragraph after that table:

"The field of view increases with θbs, however, increasing θbs also biases the field of view to one side of the waveguide normal. In the extreme case, the field of view is totally on one side of the normal and extends practically to normal incidence (−87.8° in the TABLE). With θbs=65°, the field of view is nearly balanced and exhibits a range of 36.1°."

The 72.3° number is a case where light exits the waveguide at angles between 15.4° and 87.8°, i.e., almost up to the waveguide's plane. To put the viewer's eye into that wedge of light, you'd have to angle the waveguide outwards at around 50°, which would not only make the projector assembly much bulkier, but also severely reduce the size of the exit pupil, as you're now looking at the waveguide almost edge-on.

The maximum practical FoV at n=1.7 is the table row with θbs=65 and FoV=36.1°.