Microelectromechanical systems

Microelectromechanical systems (MEMS) are micrometer-scale devices that combine mechanical and electrical components on a single chip, built with fabrication methods that came from the integrated circuit industry. A 2022 review in Micromachines describes MEMS devices as ranging in size from several micrometers to several millimeters, with silicon as the main material, and notes that the same field is called Microsystems Technology in Europe and Micro Machines in Japan.

MEMS parts are found throughout virtual reality and augmented reality hardware. The gyroscopes and accelerometers inside a headset's inertial measurement unit (IMU) are MEMS sensors, and the first Oculus Rift Development Kit tracked head orientation with a MEMS-based IMU. On the display side, tiny MEMS mirrors steer laser beams in laser beam scanning (LBS) projectors such as the one in Microsoft HoloLens 2, and the digital micromirror device behind Texas Instruments' DLP technology is also a MEMS chip. MEMS microphones are sold for smart glasses and AR/VR systems, and MEMS scanners for eye tracking and MEMS loudspeakers have been developed for the same devices.

Reviewed 27 September 2026. Checked every cited source (Chircov 2022, Gill 2022, DARPA, NIHF Hornbeck, LaValle et al. 2014, Xiong et al. 2021, The Verge, UploadVR, TechCrunch, Road to VR, Bosch, TDK, MicroVision, AdHawk, Li et al. 2025, xMEMS) against the claims, figures and quotes they support. About review dates.

Definition and fabrication

Chircov and Grumezescu define MEMS as "micrometer-scaled precision devices, which combine mechanical and electrical components to accomplish tasks that are normally carried out by macroscopic systems". The most common MEMS devices are transducers (sensors and actuators), and they are generally produced with micromachining techniques adapted from integrated circuit manufacture. The review groups the lithographic fabrication methods into three main families: bulk micromachining, which shapes the substrate itself with etchants; surface micromachining, which builds structures from patterned films on top of the substrate; and LIGA techniques.

DARPA, which funded MEMS research heavily from 1994, describes the approach as adapting "standard semiconductor-fabrication methods to fabricate miniature mechanical structures such as flexible membranes, cantilevers, and even trains of interdigitated gears", which were then integrated with electronics. The same review lists everyday MEMS products that include image, touch, distance, pressure, temperature and humidity sensors, microphones, gyroscopes, accelerometers and magnetometers.

History

According to Chircov and Grumezescu, the first MEMS devices were commercialized in the early 1980s, when MEMS pressure sensors and accelerometers came into wide use in the automotive industry. At Texas Instruments, Larry Hornbeck invented the digital micromirror device (DMD) in 1987 after about a decade of work on analog micromirrors. The DMD is an array of up to two million hinged microscopic aluminum mirrors on a silicon chip that tilt thousands of times a second to create an image by directing pulses of light; it is the imaging technique behind Texas Instruments' trademarked DLP technology.

Vibrating MEMS gyroscopes followed later in the 1980s. A 2022 review in Sensors by Gill and colleagues dates the first micromachined gyroscope to 1988 at the Draper Laboratory, a design with no rotating parts, and describes how such devices vibrate a mass at resonance: when the chip rotates, the Coriolis effect shifts part of that vibration into a perpendicular direction, and the size of this second motion gives the rotation rate. The review says MEMS vibrating gyroscopes gained attention over the previous two decades because of their low power consumption, easy integration and low fabrication cost.

DARPA targeted inertial navigation devices, lab-on-a-chip biological detectors, and optical switches and displays in its MEMS program, and says its support added "consequential momentum" to a field that grew into a multi-billion dollar market.

Applications in VR and AR

Inertial sensors and head tracking

In their 2014 paper on head tracking for the Oculus Rift, Steven LaValle and colleagues at Oculus VR wrote that Palmer Luckey's 2012 prototype, which John Carmack used for a Doom demo at E3, "convinced industry leaders that a low-cost, high-fidelity VR experience could be achieved by leveraging MEMS sensing and video display technology from the smart phone industry". The Rift Development Kit had to meet its tracking requirements with "a simple MEMS-based inertial measurement unit". Its sensor board combined an Invensense MPU-6000 (gyroscope plus accelerometer) and a Honeywell HMC5983 magnetometer, each giving three-axis readings, and reported sensor observations at 1000 Hz.

The paper describes the main problem with MEMS gyroscopes in this role. Integrating angular velocity gives orientation, but calibration errors and temperature dependence leave a systematic error that accumulates as drift. The Oculus team corrected tilt drift with the accelerometer's measurement of gravity and yaw drift with the magnetometer, and used the 1000 Hz gyroscope data for predictive tracking to hide part of the 30 to 50 ms latency of a typical system at the time.

MEMS IMU makers now market parts specifically for XR. TDK InvenSense sells its ICM-45685 6-axis IMU as "purpose-built for smart eyewear and wearable applications", and lists head tracking and orientation sensing among its uses in smart glasses and AR/VR systems. At CES 2026, Bosch Sensortec introduced its BMI5 inertial sensor platform, including a BMI560 variant optimized for XR headsets and glasses, where the company said low noise, low latency and precise time synchronization support natural head motion, frame prediction and 3D interaction; a BMI563 variant for XR controllers has an extended full-scale range. Bosch quoted a latency below 0.5 ms and said the product line was planned to enter high-volume production from the third quarter of 2026.

Scanning mirrors and display engines

In a MEMS laser beam scanning engine, micromirrors scan red, green and blue laser beams directly to form a two-dimensional image, either with one two-axis mirror or with two one-axis mirrors, and gray levels come from pulse-width modulation of the laser diodes. A 2021 review of AR and VR displays by Xiong, Hsiang, He, Zhan and Wu found that MEMS-based LBS had the highest luminous efficacy of the light engines it compared (about 40 lm/W, since the mirror itself loses almost no light), a very compact form factor, and a contrast ratio that can reach 10⁶:1 because the lasers switch off fully for black. Its main limitation was frame rate: a 60 Hz image at around 1K resolution already needs a mirror resonant frequency of around 50 kHz, and the 60 Hz frame rates demonstrated so far could cause flicker. The same review lists the DMD as a separate reflective light engine for AR, with a binary frame rate that can reach 30 kHz.

The HoloLens 2 uses a MEMS laser scanning display. In The Verge's hands-on, Dieter Bohn wrote that its lasers "shine into a set of mirrors that oscillate as quickly as 54,000 cycles per second so the reflected light can paint a display", and that the two together "form the basis of a microelectromechanical system (MEMS) display" whose image is fed into waveguides. Zulfi Alam, Microsoft's general manager for Optics Engineering, told Bohn that because the mirrors oscillate in resonance they need less energy to move, and that the system used less power than the alternative. Microsoft confirmed in October 2024 that HoloLens 2 production had ended, and said updates for critical security issues would continue until 31 December 2027.

Several smart-glasses designs used a MEMS scanner with a holographic element in the lens instead of a waveguide, a form of retinal projection. Writing for UploadVR in 2019, Chris Grayson described laser displays in which the beam is "typically" steered by "a MEM Chip with a nano-scale mirror mounted on a dual-axis gimbal", naming Focals by North as the most notable example; he noted that this through-the-air projection can be blocked by anything between the temple and the lens, such as hair. Intel's Vaunt glasses, shown in February 2018, projected a red, monochrome image of about 400 x 150 pixels from a VCSEL laser onto a holographic reflector in the right lens; Intel's Jerry Bautista told The Verge that the team had to integrate "MEMS devices for actually painting an image". Intel confirmed in April 2018 that it had abandoned the Vaunt project.

Bosch Sensortec presented its Smartglasses Light Drive module at CES 2020. Inside it, a MEMS-based collimated light scanner scans a holographic element embedded in the lens, which redirects the beam onto the retina. Bosch gave the module's weight as under 10 grams, called it the smallest light drive on the market with 30 percent less depth, and said it would be available to high-volume manufacturers in 2021 as part number BML500P. MicroVision, whose PicoP scanning technology is based on laser beam scanning, agreed in 2016 to co-market MEMS mirror-based LBS solutions with STMicroelectronics for pico projection and head-up displays; the companies said they also expected to target emerging VR and AR applications.

DMD chips have also been used in head-mounted displays. Road to VR reported from CES 2014 that Texas Instruments chose Avegant to be the first to integrate its newer DLP chips, with reduced spacing between adjacent mirrors, in the Avegant Glyph, and that the screen door effect was "almost eliminated" in the prototype.

Eye tracking

MEMS scanners have been proposed as a lower-power alternative to camera-based eye tracking. AdHawk Microsystems launched its MindLink eye-tracking glasses for researchers and clinicians in March 2021, saying its system "replaces cameras with ultra-compact micro-electromechanical systems (MEMS) that eliminate power-hungry image processing" and captures gaze 500 times per second. In academic work, a 2025 Micromachines paper by Li and colleagues built an eye tracker around an electrostatic two-axis MEMS mirror that sweeps a laser in a Lissajous pattern over an artificial eyeball, with the reflection read by a linear photodiode array. The authors reported a minimum resolution of 0.6 degrees and wrote that the system could later be integrated into wearable glasses.

Audio and thermal components

Headsets and glasses use MEMS microphones for voice input. TDK InvenSense markets its SmartSound MEMS microphones, including the T5848 with an ultra-low-power Acoustic Activity Detect feature, for smart glasses, alongside MEMS motion sensors and ultrasonic time-of-flight sensors.

MEMS loudspeakers are a newer category. xMEMS Labs announced Sycamore in November 2024 as a full-range, all-silicon, near-field micro speaker 1 mm thin and weighing 150 milligrams, aimed at smart watches, smart glasses, AR and VR headsets and open-fit earbuds; the company planned sampling in the first quarter of 2025 and mass production from October 2025. In August 2025 xMEMS said it would show AI glasses prototypes using Sycamore, quoted there as a 1.28 mm package, together with its µCooling fan-on-a-chip for active cooling inside the frame.

See also

• Inertial measurement unit
• Gyroscope
• Accelerometer
• Magnetometer
• Laser beam scanning
• Virtual retinal display
• DLP
• Sensor fusion
• Head tracking