In June 2021, Patently Apple posted a detailed IP report titled "Apple Invents an HMD to work with a camera accessory that will make the public aware that the user is recording video & more." Due to the anger that Google Glass generated for being able to film people without their knowledge, Apple designed an accessory for their future headset that would allow outsiders know when the HMD camera was on and filming live. 

Yesterday, the U.S. Patent and Trademark Office officially granted Apple a patent for a similar invention, but this time the indicator isn't an accessory but rather an integrated part of a future headset. Apple noted that the "status indicator may be used to indicate the current operating mode of the camera."

At one point in the granted patent Apple's notes that "Liquid crystal display devices panels may be used for the left and right display devices in alignment with the user's left and right eyes, respectively. In other configurations, the display includes a single display panel that extends across both eyes or uses other arrangements in which content is provided with a single pixel array.

The display is used to display visual content for a user of the HMD. In some configurations, a real-world image may be captured by a camera (e.g., an outwardly facing camera) so that computer-generated content may be electronically overlaid on portions of the real-world image (e.g., when the device  is a pair of virtual reality goggles with an opaque display).

At one point in the patent Apple describes advanced aspects of the camera(s) that their future headset is to implement. Apple notes that input-output circuitry may include sensors that may include, for example, three-dimensional sensors (e.g., three-dimensional image sensors such as structured light sensors that emit beams of light and that use two-dimensional digital image sensors to gather image data for three-dimensional images from light spots that are produced when a target is illuminated by the beams of light, binocular three-dimensional image sensors that gather three-dimensional images using two or more cameras in a binocular imaging arrangement, three-dimensional lidar (light detection and ranging) sensors, three-dimensional radio-frequency sensors, or other sensors that gather three-dimensional image data), cameras (e.g., infrared and/or visible cameras with respective infrared and/or visible digital image sensors), gaze tracking sensors (e.g., a gaze tracking system based on an image sensor.

As shown in FIG. 2 below, the HMD device may include components such as camera #50 and a light-emitting component such as status indicator #52 that may be used to indicate the current operating mode of the camera.

Cameras and camera indicators can be mounted in any suitable location within the device (e.g., under transparent housing structures, in alignment with holes or transparent regions in the housing #30 that serve as camera and indicator light windows, etc.).

In the illustrative example of FIG. 2, the camera and indicator have been mounted under a transparent member (#54) in an outwardly-facing location where the camera can capture images of external objects such as object #58 and where the indicator can emit light in the direction of the object (e.g., to serve as a visual status indicator for a person in the camera's field of view). 

It may be desirable to use the indicator to indicate the current state of camera.  For example, when the camera is actively gathering video (or is turned on and ready to capture an image when a shutter release button is pressed) the indicator can produce first illumination (e.g., a first color and/or a first still and/or moving light pattern). When the camera is turned off or is otherwise inactive and not capturing video or other images (and/or is deactivated so as to be incapable of capturing images), the indicator can produce second illumination (e.g., a second color and/or a second still and/or moving light pattern). 

As an example, the indicator may be red when the camera is capturing a moving image (video) and can be green or dark when no video is being captured.

Apple's patent FIG. 2 is cross-sectional view of an illustrative of an electronic device such as an HMD; FIGS. 4 and 7 illustrate an illustrative status indicator in both round and Octagonal designs.  

As with most Apple inventions/patents, they note that the invention could possibly apply to other devices in the future such as a MacBook, iPad, iPhone and/or Apple Watch. It would be great on a MacBook so as to notify users that a hacker has just turned on your camera. Many users today tape the camera when not in use. A new kind of indicator light would be appreciated.   

Without the context of Apple's June 2021 patent application that we extensively covered, it would almost be impossible to understand today's granted patent which is the technical side of their 2021 invention.

For finer details, review Apple's granted patent 11650484.