The screen is an important part of the mobile phone, a window for the user to obtain graphic information. Therefore, the importance of the color and performance of the screen is self-evident. Since August 2014, we have decided to conduct a separate objective test and experience evaluation for the screen portion of the mobile phone. Up to now, we have accumulated a total of 99 models of mobile phones of various brands, as well as 10 tablets and notebooks, and of course some are due to test models or unpopular reasons are not published on the Soomal website.
Rating method
Screen rating is divided into quantifiable color performance and subjective experience. Mobile phones are commonly used devices. Professional color performance is not necessarily directly reflected in the daily experience and the concerns of ordinary consumers. Although everyone understands the truth, the chart of objective test scores occupies most of the content of the article, but for most readers, the conclusions and achievements that you want to see are not necessarily grayscale and color, but brightness, view angle, or whether color is bright and vivid, as well as flicker, delay, smoothness and so on. We will inspire from the Soomal Reality Camera Mark Mobile and will also score the comprehensive performance of the mobile phones¡¯ screen. For professional readers, the color performance of the screen can still be analyzed through the test chart, and the non-professional readers can also intuitively understand the mobile phone screen color and experience through the score.
Soomal Mobile Display Mark will be divided into two separate sections: Experience score and Professional Color Performance score. The experience is more focused on visual and operational use; professional color is the color reproduction capability of the mobile phone screen. The experience depends on the quality of the display panel, the process, the quality, the lamination and other hardware factors, and the color performance is determined by the technical adjustment of the manufacturer. There is a certain relationship between the two. Poor panel quality leads to the bad viewing angle and whitish screen. But good color performance, or excellent color, brightness and visibility, but the color performance is a mess, these situations exist, so we need to evaluate the two independently, instead of simply adding.
Experience
In the experience, there are a total of 5+1 evaluation items, including outdoor brightness, reflective polarization, viewing angle, color details, screen quality, and an additional special feature plus.
Testing Item | Scoring | Description |
Outdoor brightness | 10 | Highest and stable brightness |
Reflective polarization | 10 | Screen reflection, polarization dimming |
Viewing angle | 10 | Screen color and contrast distortion and attenuation at the viewing angle |
Color detail | 10 | Color, resolution |
Screen quality | 10 | Screen backlight uniformity, flickering, etc. |
Extra points | 5 | Unique technologies that have greatly improved the experience. |
In addition to the extra features, the score of 10 for a single score is currently close to the standard. A score of 10 means that there are no serious defects in the single item that have a negative impact on the experience. To encourage technological innovation and progress, 10 points are not the upper limit individual scores., if there is a part of the screen performance that is better than the mainstream high price smartphones, there will be extra points.
Outdoor brightness: Brightness is the most intuitive experience that affects the use of the phone outdoors. If the highest brightness is too low, the readability will seriously be affected. Also, the highest brightness will affect the playback of HDR video and photos. The unit of brightness is cd/m2.
Reflective Polarization: The degree of reflection of the screen panel and glass and the polarization treatment. If the reflection is high, it will directly affect the viewing angle of the screen and outdoor visibility. If there is a problem with the polarizing dimming filter, the user may have missing screen content and backlight when using the mobile phone in sun glasses.
Viewing angle: The screen is at an angle to the angle of view (¡Ü45¡ã) in the horizontal hand-held state, and the screen color and contrast distortion are observed. Generally, distortions such as whitening, ash, color cast, and red-green convergence will occur, and the degree of influence on the influence of graphic reading will be evaluated.
Color details: The color and resolution of the screen. Whether the color is vivid and bright, there is serious color overflow, color block, color rigid and color dynamic missing, severe color shifting, etc., whether the resolution [PPI] is high enough.
Screen quality: The degree of PWM flicker on the screen, the brightness of the screen flashing bright and dark. As well as the consistency of the screen backlight or illumination, the consistency test takes the grayscale and brightness contrast test on the upper, middle and lower areas of the screen to check whether the screen has the same color and brightness.
Extra points: The model has some unique technical features and has sufficient advantages in actual use, such as ultra-high refresh rate.
Professional Color
In the professional color performance score of the mobile phone screen, it will be divided into five items, including grayscale, Gamma2.2, color and gamut coverage in sRGB mode, and the practicality of color management.
Testing Item | Scoring | Description |
Gray scale accuracy | 10 | Average grayscale error |
Gamma2.2 | 10 | Is the Gamma curve straight and coincident? |
Color accuracy | 10 | Screen color and contrast distortion and attenuation at the viewing angle |
Gamut range | 10 | sRGB color gamut coverage |
Color management | 10 | Color performance in different color modes |
Gray scale accuracy: The accuracy of the screen when displaying gray scale, the unit is ¦¤E, the lower the error value, the better. The average value of the score here is the evaluation standard.
Gamma 2.2 error: The standard gamma value of the sRGB and P3 color modes is 2.2 in static images. The Gamma value is a slope, and when the Gamma is 2.2 in the sRGB color range, the brightness change is consistent with the human eye perception change. Below 2.2, the contrast is insufficient. Above 2.2, the contrast of the image increases. The closer to the 2.2 standard value, the more accurately the image contrast can be reflected. Also check whether the curves of red, green and blue are coincident from the Gamma curve. Generally, it is a basic accuracy level within the range of ¡À0.1, and the error of ¡À0.2 or more is obviously insufficient contrast/too high. Too low will cause the insufficiency the color transition, and too high will result in a higher color gradient color blocks. We take the absolute value of the difference obtained by the Gamma score minus 2.2 on the screen as the judgment.
Color accuracy: refers to the perceived difference between the actual color and the displayed color. The lower the average error value and the maximum error value, the better. We take Calman's 24-color block test as the standard.
Color management function: refers to whether the mobile phone system provides a manual color gamut mode switching or adaptive color management mode, and a way to improve the color temperature of the screen display, which relates to whether the original color of the image can be finally displayed.
Similar to the experience, the professional color score item is based on the current Soomal screen evaluation of the median in the rankings and the standard is 10 points. If the individual performance is higher than the standard, the extra points can be obtained.
Example
Here, we use a mobile phone as an example to rate the template.
The final two total scores do not add up.
Testing Item | Performance | Score |
Outdoor brightness | 649 peak brightness, excellent | 13 |
Reflective polarization | No obvious reflection | 10 |
Viewing angle | Bluish, no impact to readibility | 10 |
Color detail | Vivid and high resolution | 12 |
Screen quality | Flickering under 20% brightness | 9 |
Extra points | - | 0 |
Total Score | - | 54 |
Testing Item | Performance | Scoring |
Gray scale accuracy | ¦¤E1.53 | 12 |
Gamma2.2 | 2.22 | 10 |
Color accuracy | Average ¦¤E1.15£¬Max ¦¤E2.09 | 12+7 |
Gamut range | 100.5% | 11 |
Color management | sRGB, P3 supporting, ¦¤E<3 | 5+5 |
Total Score | - | 62 |
iPhone Xs Max will be the first mobile phone to use this set of ratings, and will also complement the mainstream models this year. As it is a beta version, we will continue to fix and improve this set of scoring standards.