The previous survey resulted in a new proposal for a note by combining the strengths of the two original proposals, with a few edits. Please review the new proposal and indicate whether this note is ready to incorporate or needs further work.

Note 2: Examples where a density-independent pixel may not be defined in the platform:

• Software designed for specific hardware, such as kiosks or office equipment, where the author knows the physical screen size and, potentially, the pixel density.
• Software, such as streaming apps on smart TV platforms or similar software, where the author may lack information about the physical screen size but may know an appropriate viewing distance or viewing angle.

When there is no platform-defined density-independent pixel measurement, the reference pixel size can be approximated in the following manner:

• Determine a viewing distance: The chosen viewing distance should align with the use case and display type. For instance, in the case of a touchscreen, the viewing distance should be less than the length of an arm, typically around 28 inches (71 cm).
• Calculate the length of the reference pixel: Divide the viewing distance (v) by 2688.

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Review proposed note 3 (which was reviewed as note 6 in the previous survey), and answer the question. In the input field, indicate whether further edits are needed and make suggestions for changes.

Note 3: Most software and devices are usable at more than one viewing distance. However, for a density-independent pixel to be considered an approximation for the reference pixel, the viewing distance of the visual-angle pixel must be plausible. For example, in software designed for use with a touchscreen, a visual-angle pixel longer than 0.11 inch (0.28 mm) would not be plausible, because this would signify a viewing distance of more than arm’s length.

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Review proposed note 4 (in the last survey this was reviewed as proposed Note 7), and answer the question. There are a few small edits based on the survey - replaced "visual-angle pixel" with "device-independent pixel", "midrange" with "typical", and added in the SC numbers for Target Size and Focus Appearance. In the input field, indicate whether further edits are needed and make suggestions for changes.

Note 4: People with low vision often use devices at less than the standard viewing distance. However, basing the device-independent pixel on a typical viewing distance provides a balance of benefits for users with disabilities. If a longer viewing distance were chosen as the basis for the device-independent pixel, the viewport would be measured with a smaller number of larger pixels, causing Success Criterion 1.4.10 Reflow to be less stringent. If a shorter viewing distance were chosen, user interface components would be measured with a larger number of smaller pixels, causing the 2.5.8 Target Size and 2.4.13 Focus Appearance criteria to be less stringent.

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