Transparent OLED Pixels are Partially Clear
Each pixel in a transparent OLED display is made up of 4 sub-pixels. Color is created by the combination of the red, green, and blue sub-pixels and the remaining area of the pixel is clear. That clear section creates the transparency.
This is why there is a direct relationship between resolution and transparency. If the display contains more active pixels, that creates less space for the clear pixels and results in a display that is less see through.
Black is Clear, White is Opaque
Unlike transparent LCD displays, black or dark content on the screen is clear and white or bright content is opaque. You can see this in the photos below. The car image appears to be floating in space and through the black background you can clearly see the books and pencils which are physical objects set behind the display. The full screen image of the boat appears in the foreground, but if you look closely at the hull of the boat you will see some objects behind the display, made visible by the dark area.
White or bright content will be opaque and will shine from the screen and appear in the foreground
Ambient Light Affects Perceived Transparency
Just like any glass surface, ambient light affects that appearance of transparency. The two images below are the same display, the same on-screen content (of the model), and the same plant behind the display. The only difference is that the plant has been “uplit.” With more light on the object behind the screen you can see that the leaves of grass are much more visible through the display than they would be if the light was off. A transparent display in an entirely dark room will appear opaque. A transparent display in a light filled room with objects or scenes heavily lit behind the display will appear like transparent glass.
Left: No uplight. Display looks more opaque. Right: Plant is uplit. Display looks more transparent.
Readability Makes Exhibits Possible
Transparent display can be quite clear, which makes reading fine details or text on objects behind the display possible. This means that retail merchandisers or museum exhibit designers could put the display in front of goods or artifacts without obscuring their view.
Pencils and book titles are readable through display. Objects dozens of feet or meters behind the display are viewable.
Broad Color Gamut Reads as Brightness
Transparent OLED technology has long been recognized for its amazing color performance. While best-in-class LCD displays achieve around 72% NTSC color space (a measure of the number of colors that the display is capable of showing), OLED can achieve greater than 100%. This means more vivid reds, more vibrant greens, and eye-popping blues.
This color performance, together with the peak brightness characteristics of the emissive display, create a display that appears much brighter than you might expect from reading the specifications alone. Your eye translates color as brightness and in a side-by-side comparison with a “brighter” display, the transparent OLED will be the most vivid.
Greater than 100% NTSC. Colors like highly-saturated red are stunning on the display and because of the wide viewing angle, eye-catching from afar.