Microsoft aurait réussi a doubler le FOV des Hololens

In accordance with certain embodiments of the present technology, an optical waveguide includes at least two intermediate-components, each of which is used to support a different part of a FOV. More specifically, the input-coupler is designed to diffract light in at least two different (e.g., opposite) directions in order to guide light corresponding to an image to different intermediate-components. For example, by appropriately tuning the grating periods of the input-coupler, light corresponding to a left portion of a FOV is steered to a left intermediate-component, and light corresponding to a right portion of the FOV is steered to a right intermediate-component. Additionally, grating periods can be appropriately tuned so that part of the FOV (e.g., a central portion of the FOV) that is not to be steered to either of the left and right intermediate-components goes to an evanescent diffraction order that does not carry any power. More generally, through proper design and placement of an input-coupler and proper placement and design of two or more intermediate-components, different parts of a FOV can be guided in different directions. Such embodiments can provide two significant advantages. First, such embodiments can provide for a total diagonal FOV that is very large, even though each of the intermediate-components individually support a relatively smaller FOV (e.g., a diagonal FOV of no more than about 35 degrees). Additionally, since only a desired part of a FOV is guided in each of the different directions, there can be significant power savings (e.g., of up to 50%). Demonstrations of embodiments of the present technology have shown that such embodiments can be used to obtain a diagonal FOV of up to about 70 degrees, where the index of refraction of the bulk-substrate of the optical waveguide is about 1.7 (i.e., nl ~ 1.7). Accordingly, it has been demonstrated that embodiments of the present technology can be used to double the diagonal FOV, compared to the FOV that could be achieved using the exemplary waveguide 100 described above with references to FIGS. 1A, IB, 1C and 2. Through proper design, embodiments described herein can be used to provide even larger FOVs of up to about 90 degrees. It is noted that the term FOV, as used herein, refers to the diagonal FOV, unless stated otherwise.