top of page
  • Writer's pictureMaymay

From Tiny Screens to Immersive Worlds: The Journey of Microdisplay Technology

What is a Microdisplay?


A microdisplay is a display with a very small screen, typically less than two inches diagonal. Introduced in the 1990s, microdisplays initially served as image sources for rear-projection TVs (RPTVs), projectors, viewfinders in digital cameras, and helmet-mounted display systems (HMDs).


Today, the demand for wearable products has surged, leading to a significant expansion of the microdisplay market. Key applications for high-resolution microdisplays now include augmented reality (AR) and smart glasses, helmet-mounted displays, virtual reality (VR) systems, and head-up displays (HUDs). These applications require advanced microdisplays that offer excellent picture quality, high brightness, and low power consumption. Recent advancements have seen the development of OLED microdisplays with brightness levels reaching up to 15,000 nits, with future projections aiming for 30,000 nits​​.


The global microdisplay market, valued at $2.1 billion in 2023, is expected to grow at a compound annual growth rate (CAGR) of 17.6% to reach $9.2 billion by 2032​ (Research & Markets)​. This growth is driven by the increasing popularity of AR/VR technologies, which require sophisticated microdisplays to deliver immersive experiences.


Outline of the Blog

1.     What is a Microdisplay

2.     Types of Microdisplay Technologies

3.     Technologies and Main Manufacturers

4.     Microdisplay Technologies Used in AR and VR Systems

5.     Overview of Microdisplay Types Used in Metavision’s Products


Types

There are various microdisplay technologies, with the mainstream ones including liquid crystal on silicon (LCOS), liquid crystal display (LCD), digital micromirror device (DMD), digital light processing (DLP), OLED on silicon (OLEDOS), and MicroLED.


In the wearable technology field, especially in augmented reality (AR), virtual reality (VR), mixed reality (MR), and extended reality (XR) applications, four main types of microdisplay technologies are prominent:


  • LCD microdisplays are commonly used due to their availability and cost-effectiveness.

  • MicroOLED microdisplays offer high contrast, vibrant colors, and fast response times, with recent advancements pushing brightness levels to 15,000 nits and higher​.

  • MicroLED technology is gaining traction due to its high brightness, low power consumption, and durability, making it ideal for future AR/VR headsets​.

  • LCoS microdisplays provide high resolution and good image quality, making them suitable for detailed visual applications​.


Technologies and Main Manufacturers

An LCD (Liquid Crystal Display) works by using liquid crystals to control the passage of light. The display is made up of several layers, including two polarizing filters and a liquid crystal layer sandwiched between two transparent electrodes. In its natural state, the liquid crystals are twisted, rotating the light's polarization so it can pass through the second polarizer, allowing light to be seen (white state). When a voltage is applied, the liquid crystals align straight, preventing the light's polarization from rotating and causing the light to be blocked by the second polarizer (black state).

By adjusting the voltage at different points on the screen, the alignment of the liquid crystals can be controlled, allowing varying amounts of light to pass through and creating different shades of gray. Color displays achieve this by using red, green, and blue sub-pixels. An LCD requires a backlight as it does not produce its own light. This backlight shines through the layers, enabling the display of images.


BOE Technology Group is one of the biggest and most prominent manufacturers in the LCD field. BOE is known for its extensive production capabilities and technological advancements, particularly in high-resolution displays such as 8K LCD panels.



Structure of a LCD device


Source: ResearchGate

 

LCoS (Liquid Crystal on Silicon) is a reflective display technology that uses liquid crystals applied to a silicon backplane to control light. In an LCoS display, light from an external source is polarized and directed onto the liquid crystal layer. The liquid crystals, whose alignment is controlled by the voltage applied via the silicon backplane, modulate the light's polarization. In the "off state," the light's polarization remains unchanged and is reflected back. In the "on state," the liquid crystals alter the light's polarization, allowing it to pass through a polarizing beam splitter (PBS) and an analyzer, thus creating an image.

LCoS microdisplays are particularly valuable in applications requiring high resolution and high contrast ratios, such as AR/VR headsets, projectors, and head-up displays (HUDs). These microdisplays can achieve extremely high pixel densities and precise light control, making them suitable for immersive and detailed visual experiences. Despite their advantages, LCoS displays require careful optical alignment and often involve more complex and costly manufacturing processes compared to other display technologies. Nonetheless, their superior performance in terms of resolution and image quality makes them an excellent choice for advanced display applications.

Structure of LCoS

Source ResearchGate

 

OLED (Organic Light Emitting Diode) technology uses organic materials that emit light when an electric current passes through them. An OLED display consists of several layers, including a transparent anode, a cathode, and organic layers, such as the electron transport layer, emissive layer, and hole transport layer. When voltage is applied, electrons and holes move towards the emissive layer where they recombine to form excitons, releasing energy in the form of light. OLEDs do not require a backlight, allowing for thinner and more flexible screens with high contrast ratios, vibrant colors, and fast response times. This makes OLEDs popular in a variety of devices, including smartphones, televisions, and monitors.


MicroOLED (Micro Organic Light Emitting Diode) technology is a specialized form of OLED designed for small, high-resolution displays, typically less than an inch in size. These microdisplays retain the same basic structure and operational principles as larger OLEDs but are optimized for applications like AR/VR headsets, camera viewfinders, and wearable devices. MicroOLEDs offer exceptional pixel density, high contrast ratios, and excellent image quality, making them ideal for applications requiring compactness and precision. The absence of a backlight allows for thinner, more efficient displays, although the manufacturing process can be more complex and costly. Despite these challenges, the superior performance of microOLEDs in terms of clarity, brightness, and efficiency makes them highly suitable for high-end, specialized applications.


Sony is a leading producer of MicroOLED displays, known for their exceptional quality and performance. Sony’s MicroOLED technology is utilized in various high-end applications, including AR/VR headsets and professional camera viewfinders. The displays offer high resolution, fast response times, and excellent contrast ratios, which are essential for immersive and detailed visual experiences. Sony’s significant role in providing MicroOLED displays for devices like the Apple Vision Pro underscores their position as a key player in the market.


Seeya: Seeya is another major supplier of MicroOLED displays, focusing on high-resolution and low-power consumption designs. Their displays are widely used in AR/VR devices and other near-to-eye applications. Seeya’s technology emphasizes compactness and precision, offering superior image quality and pixel density.


BOE Technology Group:  Their MicroOLED displays are known for their high resolution, excellent brightness, and efficiency, making them suitable for a variety of advanced applications such as AR/VR headsets and high-precision instruments. BOE has also made significant strides in developing 8K MicroOLED displays.

Structure of OLED

Source: Futaba

 

MicroLED technology uses microscopic light-emitting diodes to create displays with high brightness, efficiency, and durability. Unlike traditional displays that rely on a backlight, each microLED in a display emits its own light, allowing for precise control over brightness and color at the pixel level. This results in exceptional image quality with high contrast ratios and vibrant colors. MicroLED displays are also highly energy-efficient and have a longer lifespan compared to OLEDs, making them ideal for applications in AR/VR headsets, smartphones, and wearable devices.


BOE is pioneering MicroLED technology with innovative prototypes like the MicroLED Transformer Display. This display features flexible, high-brightness panels that can seamlessly connect to form larger screens. By using monolithic integration, where microLED arrays are directly integrated onto a substrate, BOE achieves high pixel density and superior display quality. This approach enhances scalability and efficiency, making MicroLEDs suitable for a wide range of advanced display applications.

Jade Bird Display (JBD) is another prominent player in the MicroLED technology landscape. JBD utilizes a hybrid monolithic integration approach for its MicroLED displays, which involves directly integrating semiconductor emitters onto a silicon backplane. This method enables high-resolution, high-brightness displays ideal for AR and VR applications. JBD's MicroLED technology is known for its exceptional light efficiency and ability to produce displays with up to 1 million nits of brightness. Their advanced manufacturing techniques result in compact, high-density pixel arrays that provide superior image quality, making them a critical supplier for next-generation microdisplays​​.

Structures of LCD, MICROOLED, MICROLED

Source: Delmic


MicroDisplays Technologies Used in AR and VR Systems

The selection of microdisplay technology for augmented reality (AR) and virtual reality (VR) systems significantly impacts overall system performance, influencing parameters such as display luminance, contrast ratio, color accuracy, uniformity, exit pupil size, and system resolution. It also affects the physical attributes of the device, including size, weight, and cost. Understanding the differences between various microdisplay technologies—LCD, LCoS, MicroOLED, and MicroLED—is crucial for making informed decisions that balance performance with practicality.


LCD microdisplays are known for their cost-effectiveness and maturity, providing decent resolution and color performance. However, they require a backlight, which can increase the system's size and power consumption.


LCoS displays offer high resolution and good color reproduction, making them suitable for applications requiring detailed imagery, though their complexity and integration challenges can limit their practicality in compact systems.

Based on the current market trends and the evolving landscape of microdisplay technologies, LCoS (Liquid Crystal on Silicon) appears to be the less critical technology among them. While LCoS offers high resolution and excellent image quality, its applications are more niche compared to LCD, MicroOLED, and MicroLED.


MicroOLED displays stand out for their excellent contrast ratios, fast response times, and high pixel density, making them ideal for high-end AR/VR applications where image quality and compact form factor are paramount. However, they can be more expensive and complex to manufacture.


MicroLED technology, while still emerging, promises exceptional brightness, energy efficiency, and durability, potentially surpassing other technologies in terms of performance. However, the current high cost and manufacturing challenges need to be addressed.


For optimal AR/VR system design, integrating the microdisplay early in the development process ensures that the display technology aligns with the system's optical and performance requirements, leading to better user satisfaction and system effectiveness. Selecting the appropriate microdisplay technology can differentiate a product, offering superior performance at an acceptable volume and cost.


Microdisplay Technologies Comparison Chart.

Overview of Microdisplay Types Used in Metavision’s Products

 


Reference:



108 views

Recent Posts

See All

Comentários


bottom of page