Today the U.S. Patent and Trademark Office officially granted Apple a patent that relates to displays for head-mounted devices. More specifically, a lighting system in a VR Headset that assists a user's eyes adjust from the bright outside environment to a dark VR Headset environment and vice versa.

Head-mounted devices such as virtual reality glasses and augmented reality glasses use displays to generate images for a user.

According to Apple, if care is not taken, a head-mounted device may be cumbersome and tiring to wear. The images on the display may appear too dark and washed out when the user first puts the head-mounted device on his or her head. The user may experience dazzle or discomfort when transitioning out of a virtual reality viewing experience. The dynamic range of a head-mounted display may be perceived as insufficient depending on the adaptation state of the user's eyes.

A head-mounted electronic device configured to be worn on a user's head may include a display that generates display content and an optical system through which the display content is viewable. The head-mounted device may include a lighting system that illuminates a periphery of the optical system. When the user places the device on his or her head in a brightly lit environment, control circuitry may operate the lighting system to provide bright illumination to the user's peripheral vision. The lighting system may gradually decrease in brightness until the user transitions from a bright-adapted state to a dark-adapted state. When the user is partially or fully dark-adapted, the lighting system may be turned off and the display may be turned on. Conversely, when a user is about to remove the device from his or her head, the control circuitry may gradually increase the brightness of the lighting system so that the user can transition from a dark-adapted state to a bright-adapted state before removing the device.

In some arrangements, an ambient light sensor may measure ambient light conditions outside of the electronic device and the control circuitry may control the lighting system based on the ambient lighting conditions.

Control circuitry in the electronic device may estimate a brightness adaptation state of the user that is wearing the electronic device. The control circuitry may adjust a brightness of the lighting system based on the user's adaptation state. This may include, for example, adjusting the brightness of the lighting system based on ambient light conditions, physiological attributes of the user, motion sensor data, gaze position, and/or other information.

The lighting system may include one or more light sources. The light sources may be light-emitting diodes. The control circuitry may be configured to independently control the brightness and/or color of each light source (e.g., some light sources may be turned off while others are turned on, some light sources may have one brightness and others may have a different brightness, etc.).

In some arrangements, the light sources may include red, green, and blue light-emitting diodes or light sources of other colors so that control circuitry can adjust a color of illumination from the lighting system. The color of illumination from the lighting system may, for example, be adjusted to match or more closely match the color of ambient light so that the transition from the ambient light to the head-mounted display light is less abrupt.

Apple's patent FIG. 3 below is a perspective view of an illustrative head-mounted device having a lighting system that illuminates a periphery of an optical system.  

Apple's patent FIG. 5 above is a diagram showing how control circuitry may use information from sensors and other input-output devices to determine operating conditions for a lighting system and to determine tone mapping parameters for a display.

For more details, review Apple's granted patent 10,997,948