Apple wins a patent for a Cooling System designed to counter the heat generated by OLED Panels in a Mixed Reality Headset
Apple's engineering team behind Apple's future mixed reality headset have been working on a cooling system that could keep the heat generated by the display system away from the user's face. The first of its kind surfaced in March 2019 in our report titled "Apple Invents a Thermal Regulation System for their Head Mounted Display System." Another cooling system patent application surfaced in June 2021 in a report titled "Apple's Invents an Air-Flow System for their future Mixed Reality Headset to Keep a user's face and components cool at all times." Two of the patent images from those patents are presented below.
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Today the U.S. Patent and Trademark Office officially granted Apple a patent that once again relates to a future HMD thermal cooling system designed to keep the user's face cool when wearing the device for long periods of time.
Apple notes in their patent background that certain display panels, such as OLED and uOLED panels, for example, can operate at high temperatures. In known systems, such as wearable HMDs, for example, display panels are usually supported by a carrier, bezel, or other such structure, which is often formed from a lightweight material (e.g., plastic) to reduce the overall weight of the systems.
These structures, however, offer little benefit in terms of thermal regulation. Without proper cooling and heat dissipation, the panels (which are expensive and difficult to replace) can degrade over time, often resulting in irreparable damage or system failure. To manage and offset the heat generated by the panels during use, and thereby increase their usable life, display systems will often incorporate additional components, such as heat sinks. These additional components, however, create design challenges and add to the overall weight of the systems.
Apple's granted patent addresses these challenges by providing a display system that integrates thermal solutions into structural components. This combined functionality not only reduces the overall number of components, complexity, and weight of the display system, but increases thermal conductivity and improves thermal management to decrease operating temperatures and extend the system's usable life.
a wearable head-mounted display (HMD) is disclosed that includes an internal system housing defining an interior space and a display stack that is positioned within the interior space. In various embodiments, it is envisioned that the display stack may be either fixed in relation to the system housing or movable in relation to the system housing. The display stack includes a display panel, a carrier supporting the display panel, and a heat sink. The carrier, the display panel, and the heat sink are secured together such that they are movable in unison within the system housing to adjust focus of the display panel. The carrier and the heat sink respectively include first and second thermal solutions to facilitate heat transfer away from the display panel. Throughout the present disclosure, the term "thermal solution" should be understood to include any metallic or non-metallic material having high thermal-conductivity properties (e.g., graphite, stainless steel, copper, aluminum, magnesium, titanium, and alloys thereof, either individually or in combination) and/or any structure that is configured to facilitate the transfer of heat away from the display panel(s) disclosed herein.
In certain embodiments, the display panel may be positioned between the carrier and the heat sink.
In certain embodiments, the HMD may further include an actuator in mechanical cooperation with the display stack to reposition the display stack within the system housing.
Apple's patent FIG. 1 below is a top, perspective view of a display system configured as a wearable HMD in accordance with the principles of this granted patent; FIG. 2 is a partial cross-sectional view of the display system seen in FIG. 1 including one embodiment of a display stack.
For greater details, review Apple's granted patent 11,340,670.