Table of contents
Transparent OLED displays address the growing demand for device designs that present information without obstructing the view of elements behind the screen. Thanks to their design, TOLED technology is used wherever conventional displays would limit the field of vision. Unisystem’s portfolio includes a transparent OLED display by Winstar – the WEO012856A model, featuring a 1.51-inch diagonal and a resolution of 128 × 56 pixels. In this article, we present its key technical specifications, optical characteristics, and typical application areas in modern industrial and specialized devices.
TOLED (Transparent OLED) Technology – Operating Principle, Advantages and Limitations, Applications
Structure of TOLED Displays
TOLED technology is an evolution of conventional OLEDs, engineered so that the panel not only emits light but also allows it to pass through in both directions. Unlike traditional OLED displays, which use metal, reflective electrodes, TOLED panels incorporate transparent or semi-transparent conductive electrodes (such as ITO layers). All material layers are carefully selected and optimized to maximize light transmission from the panel itself as well as from the surrounding environment.
As a result, the entire module structure is designed to achieve high optical transparency without compromising image emission. In practice, the transmittance of TOLED panels can reach approximately 60%, enabling a clear view through the display while simultaneously presenting graphical content.
How Does TOLED Technology Work?
The operating principle of TOLED displays is the same as that of conventional OLED panels – each pixel consists of an organic diode that emits light when an electric current flows through it, eliminating the need for a separate backlight. In a TOLED structure, organic layers positioned between a transparent anode and cathode generate light directly within each pixel, ensuring excellent readability of the displayed information.
At the same time, the use of transparent electrodes allows ambient light to pass through the panel, keeping the background visible even while content is displayed.
Advantages and Limitations of TOLED Technology
Like any display technology, TOLED offers both advantages and inherent limitations resulting from its design and material properties. Below are key considerations for designing applications that incorporate transparent OLED displays.
Advantages of TOLED Displays:
- transparency – high optical transparency enables information to be displayed without obscuring the background, preserving the full field of view. This feature is particularly important in solutions such as smart glass (e.g., intelligent vehicle windows) and Head-Up Display (HUD) systems, where information is presented directly within the user’s line of sight,
- enhanced information perception – data displayed on a transparent panel appears to “float” over the real-world background, making it easier to interpret without requiring the user to shift their focal point,
- ultra-thin design – as with other OLED displays, the absence of a backlight allows for extremely thin modules, simplifying integration into compact devices,
- resistance to environmental factors – stable operation under demanding environmental conditions, including a wide temperature range (both low and high) and exposure to intense ambient lighting, including direct sunlight,
- modern aesthetics – when powered off, the screen remains nearly invisible, supporting a clean, minimalist device design.
Limitations of TOLED Displays:
- limited lifespan – organic layers may degrade faster than in certain alternative display technologies, particularly when static content is displayed for extended periods (risk of image retention or burn-in). However, it is worth noting that modern OLED materials are increasingly resistant to aging processes, and continuous advancements in manufacturing and encapsulation technologies are steadily extending the declared lifespan of modules compared to earlier generations,
- higher production cost – the use of transparent electrodes and specialized manufacturing processes makes TOLED displays more expensive than standard OLED panels.
Applications of TOLED Displays
TOLED displays serve applications from micro-optical solutions to large-format information systems. These uses include:
- head-Up Display (HUD) systems – used in automotive, aviation, and rail transport, where critical information is presented directly within the user’s field of view,
- optical and observation devices – including sights, scopes, viewfinders, vision enhancement systems, and other advanced optical equipment designed for professional applications,
- specialized measuring instruments – such as laser rangefinders, total stations, theodolites, inclinometers, and other measurement systems used in surveying, construction, and industrial environments,
- retail solutions – where transparent screens enable the presentation of marketing content on shop windows without obstructing product displays,
- modern user interfaces – for example, in consumer devices where maintaining visual aesthetics is essential, allowing seamless screen integration with the enclosure and creating a distinctive design effect.
WEO012856A – TOLED Display by Winstar
Optical Parameters
The WEO012856A is a transparent OLED (TOLED) display featuring a 1.51-inch diagonal and a resolution of 128 × 56 pixels. The pixel size is 0.254 × 0.254 mm, and their precise, uniform arrangement ensures sharp and consistent image rendering. The active area (AA) measures 35.052 × 15.324 mm, allowing clear content placement within the available display surface.
As with all OLED technologies, one of its key advantages is virtually unlimited viewing angles, ensuring that displayed information remains legible regardless of the observer’s position. This model belongs to the category of graphic OLED displays, enabling flexible presentation of text, icons, and simple graphical elements.
Thanks to these parameters, the display is well-suited for industrial applications where it is essential to present information while maintaining visibility of the background.
High Transparency
The WEO012856A offers a transparent OLED matrix with a high light transmittance rate – about 40–50% of light passes through the panel structure. You can integrate the module into glass surfaces, viewfinders, or enclosures without significantly limiting visibility of the surrounding environment.
Although designed to be transparent, the display maintains optimal readability, ensuring that displayed content clearly stands out against the background visible through the screen.
Short Response Time
The WEO012856A features a fast response time of less than 10 µs. This makes the display suitable for applications requiring dynamic content updates – without latency or unwanted visual effects such as motion blur or ghosting.
COG (Chip on Glass) Structure
The model is manufactured using COG (Chip-on-Glass) technology, in which the driver IC is mounted directly on the glass substrate. This solution reduces the module’s overall thickness and weight while improving its resistance to vibration, mechanical shock, and impact.
The display’s external dimensions are 42.04 × 27.22 × 1.2 mm, with a weight of approximately 3 g, facilitating integration into compact – including portable – devices.
Wide Operating Temperature Range
The WEO012856A is designed to operate within a wide temperature range from –40 °C to +80 °C, making it suitable for applications exposed to demanding environmental conditions. Within this specified range, the display maintains stable performance at both low and high temperatures.
Interfaces
The WEO012856A is equipped with the widely used SSD1309 controller, which supports multiple communication modes, including 8-bit parallel interfaces (6800 and 8080), SPI, and I²C. This enables flexible integration of the module with various hardware platforms.
The broad range of supported interfaces simplifies the design of the control electronics. It also allows the data transmission method to be tailored to application requirements. This applies to both communication speed and the number of available signal lines.
Supply Voltage
The WEO012856A has been designed to operate with standard electronic systems used in embedded applications. The logic section runs at a low voltage of 1.65–3.3 V, which corresponds to the levels used by most microcontrollers. As a result, additional level-shifting circuits are often not required.
The OLED matrix itself requires a higher voltage, typically 12.5 V, which is generated internally in the module. Under standard operating conditions, with about 50% of pixels active, the current consumption is around 12 mA. This results in low overall power consumption and makes the display suitable for battery-powered devices.
Lifetime (MTBF)
The use of improved organic materials translates into extended display lifetime – an aspect that was considered one of the main limitations during the early development of OLED technology. Today, the declared lifetime of individual OLED diodes can reach up to approximately 100,000 hours, depending on the emissive material used and operating conditions.
For the WEO series, the manufacturer specifies estimated operating times depending on brightness level: approximately 5,000 hours at 120 cd/m², 12,000 hours at 80 cd/m², and 15,000 hours at 60 cd/m². These values should be evaluated in the context of real operating conditions. At a typical brightness level of 80 cd/m², the declared lifetime of around 12,000 hours corresponds to more than 500 days of continuous 24/7 operation. In practice, however, most applications do not operate continuously or at maximum brightness, which means the actual service life in many systems is often longer.
Additionally, proper brightness management, the use of dimming functions, and avoiding prolonged display of static content can further extend the module’s operational lifetime.
Below is a summary of the key technical parameters of the transparent OLED display – WEO012856A from Winstar:
| Parameter | WEO012856A |
| Size | 1.51” |
| Resolution | 128 × 56 pixels |
| Emission Color | Blue (customizable) |
| Display Mode | Passive matrix OLED |
| Background Transmittance | 40–50% |
| Brightness | 120 cd/m² |
| Contrast Ratio | 10,000:1 |
| Outline Dimensions | 42.04 × 27.22 × 1.2 mm |
| Active Area | 35.052 × 15.324 mm |
| Viewing Angles | Full |
| Response Time | < 10 µs |
| Operating Temperature | –40 °C to +80 °C |
| Interfaces | 6800, 8080, 4-wire SPI, I²C |
| Controller | SSD1309 |
| Logic Voltage (VDD) | 1.65–3.3 V |
| Panel Voltage (VCC) | 7.0–13.0 V; typ. 12.5 V |
Applications of the WEO012856A by Winstar
Transparent OLED displays create new design opportunities for presenting data while maintaining full visibility of the surrounding environment. Thanks to its high transparency, excellent readability, and compact design, the WEO012856A is suitable for applications such as:
- head-Up Display (HUD) solutions – for example, in motorcycle helmets, where speed, navigation guidance, or system alerts can be displayed without requiring the rider to take their eyes off the road,
- optical sighting devices, including scopes and aiming systems – the display enables the presentation of reticles, markers, and auxiliary data without interfering with the observed image, enhancing system functionality without compromising user ergonomics,
- measuring instruments, such as laser rangefinders used in sports, hunting, or industrial applications – the transparent screen displays distance readings, angle compensation, and other measurement data without restricting the field of view.
The use of the WEO012856A from Winstar enables the design of ergonomic interfaces in which information forms a natural overlay on the real-world image, without compromising viewing comfort. Its compact 1.51-inch diagonal makes the display particularly well suited for space-constrained systems that require precise data presentation within a limited area.
Are you considering a transparent OLED display for your device design? Contact our team – we will review your project requirements together, help you select the optimal solution, and support you at every stage of implementation.
