Apple has filed for another patent (number 20190146198) for its anticipated augmented reality/virtual reality headset (the rumored “Apple Glasses”). The new filing is for an “optical system for head-mounted display.”
In the patent filing, Apple notes that head-mounted displays such as virtual reality glasses use lenses to display images for a user. A microdisplay may create images for each of a user's eyes. A lens may be placed between each of the user's eyes and a portion of the microdisplay so that the user may view virtual reality content.
However, Apple notes that ifcare is not taken, a head-mounted display may be cumbersome and tiring to wear. Optical systems for head-mounted displays may use arrangements of lenses that are bulky and heavy. Extended use of a head-mounted display with this type of optical system may be uncomfortable. Apple wants to be able to provide an improved head-mounted device.
Here’s the summary of the invention: “A head-mounted display may include a display system and an optical system in a housing. The display system may have a pixel array that produces light associated with images. The display system may also have a linear polarizer through which light from the pixel array passes and a quarter wave plate through which the light passes after passing through the quarter wave plate.
“The optical system may be a catadioptric optical system having one or more lens elements. The lens elements may include a plano-convex lens and a plano-concave lens. A partially reflective mirror may be formed on a convex surface of the plano-convex lens. A reflective polarizer may be formed on the planar surface of the plano-convex lens or the concave surface of the plano-concave lens. An additional quarter wave plate may be located between the reflective polarizer and the partially reflective mirror.”
The rumored Apple Glasses device — expected to launch next year or 2021— will be a head-mounted display for augmented reality/virtual reality games and applications. Code-named T288, it will purportedly include an 8K display for each eye and won’t have to be tethered to a Mac, iPhone, or iPad.
Of course, Apple files for — and is granted — lots of patents by the U.S. Patent & Trademark Office. Many are for inventions that never see the light of day. However, you never can tell which ones will materialize in a real product.