Display Image Update Frequency

Definition and Basic Function

This specification indicates how frequently a display updates the image shown on the screen. It's measured in Hertz (Hz), representing cycles per second. A higher value means the display redraws the image more often.

Relevance to Visual Perception

The number of times the screen is updated per second is a determinant of the perceived smoothness of motion. Higher rates generally result in a more fluid and less blurry visual experience, especially during fast-paced content like action movies or video games.

Common Values and Implications

• 60 Hz: A common standard, often sufficient for general viewing and static content. May exhibit some motion blur in faster scenes.
• 120 Hz: Offers improved motion handling compared to 60 Hz, reducing motion blur and judder. Increasingly common in modern televisions.
• Higher values (144 Hz, 240 Hz, etc.): Primarily targeted at gaming, providing extremely smooth motion and responsiveness, crucial for competitive play. Diminishing returns in perceived smoothness may be observed beyond a certain point depending on content and viewer sensitivity.

Methods of Achieving Higher Values

• Native: The panel physically updates at the specified frequency.
• Motion Interpolation (Frame Insertion): The display creates and inserts artificial frames between the existing frames to simulate a higher value. This can reduce motion blur, but may introduce artifacts like the "soap opera effect" if not implemented carefully. This is not a true physical update, but a post-processing effect.

Impact on Input Lag

Higher values, especially when native, can contribute to reduced input lag, which is the delay between a user's action (e.g., pressing a button on a game controller) and the corresponding reaction on the screen. Lower input lag is crucial for gaming and other interactive applications.

Considerations for Content Source

The benefits of higher values are most noticeable when the source content also has a high frame rate. Displaying content with a lower frame rate (e.g., 24 fps movies) on a display with a very high value may not provide significant improvements without motion interpolation.