Advantages of curved display in a perception view
In conventional studies on perception for displays, usually the main factors were lightness, brightness, chroma, contrast and so on. However, in our studies on curved displays, perceptual attributes caused by length was emerged as an important factor.
Length in our studies are the stretch of the diagonal in large display and concave depth for curved display. Our studies were conducted using 65inch UHD flat and curved displays. Every contents were moving pictures consisted of various dynamic, statistic natural scenes also artificial scenes such as animations and graphics. Those were 20sec to 15 min long. Subjective questionnaire and quantitative analysis such as eyetracker was done for results.
Before I go in to the main discourse, we achieved results that the total gazing point length for curved display is 25% less than flat display. Which the results are consistent with the previous speaker. These are outcomes by comparing eyetracker data for flat and curved displays while watching a 15min long content for each. This results can be analyzed as advantages of visual comfort or long continuous viewing situations.
The perceptual results caused by length can be categorized in to three parts. Technology variables, perceptual sense and quality preference. For Technology variables, there is speed, depth and positive depth which are quantified in length units. The perceptual sense are spaciousness and 3D effects. The quality preferences are presence and immersion. These values are a higher phase than image quality. We have found the relationship between the perceptual results and the effects among those.
We can see that the distance between the nearby and far object is physically extended for curved display - caused by the 5cm depth in a 65 inch display. When the nearby and far objects are within the middle area -50% of the horizontal -- the depth is 1.14 further than the flat display. We tend estimate length to its actual physical length. Based on these facts, participants responded that the depth is 1.15 times more than the flat display while watching moving pictures that show depth contents. This shows that we are sensing the actual physical difference as a positive advantage which the spaciousness.
The nearby object and far object is separated further more on curved display compared to flat display because of its physical curved shape. Therefore you can see that spaciousness is larger for curved display. Regardless of the contents, the distance between the near and far object for 65 inch curved display was answered to have about 15% further and 52% more of volume compared to flat display. The interesting thing here is that spaciousness is an impact factor for curved display among other perceptual senses.
Among the perceptual senses, spaciousness was a factor that occur presence. Presence-ness is as if one seems to be at a place while one is not and to experience the imaginary place physically. In other words, a feeling as if one was there. This is a value which everyone wants to achieve ultimately not only for TV image quality but also for virtual reality and even for sounds. Also, presence forms a viewing behavior of immersion. Immersion is the amount of psychological emotion one feels for reality of an imaginary world, and even feels time shortened. Conclusively, the length of curved displays creates spaciousness and spaciousness makes one feel presence and presence leads to immersion behavior.
The second perceptual sense caused by curved display is 3D effect. Generally, 3D is understood to have been caused by binocular disparity of 3D stereoscopic displays. Although 3D stereoscopic displays are most effective under perfect conditions we can also perceive 3D effect by curved display. This is due to the positive depth caused by distance among the nearby and far objects on curved displays. The advantage of this 3D effect is that it is slightly more natural.
3D effect by curved display is not as outstanding as 3D stereoscopic display forms. but it is more natural because the objects intent to be 3D are not selected and to capture attention but it is naturally layered. And this creates 3D effect that is more near to reality.
3D effect also affect presence along with spaciousness. The advantages of 3D stereoscopic display and large display occur to increase presence. Likewise, presence leads to immersion viewing behavior.
Display is moving towards virtual reality and experiencing other than just simply watching. Everyone wants to see what they have seen with their bare eyes. Everyone wants to experience what they have or what they have thought to be real. Therefore “presence” has been a key factor for quality improvement on displays. Through our studies we have found that “presence” is the most promising advantage for large curved displays and that it leads to immersive viewing behavior. Flat displays are enjoyable to watch while curved displays are to enjoyable to experience.