About Plasma Display

Hitachi 55PD8800TA, 42PD8800TA user manual About Plasma Display, Image Retention of Plasma Display

[Fig. a]

[Fig. A]

42PD8800TA 55PD8800TA

Image Retention of Plasma Display

The plasma display has one of characteristics that results in panel image retention depending on how the plasma display is used. The following are the common cases and effective usages regarding the image retention.

Characteristics of Image Retention

The phenomenon of image retention is caused by partially degrading the phosphor due to the partial display of character and ﬁ gure.

For example, when the character image as shown in Fig. A is displayed continuously for a long period of time, only the phosphors (Red/Green/ Blue) displaying the characters is degraded. Consequently, in case of displaying all white image on the entire screen as shown in Fig. a, the marks remaining by the characters will give color differences; therefore, note that it is not burnt remains of the phosphor.

The degree of image retention is proportional to the Brightness
and Display Time for the characters and/or ﬁ gures.
The brighter the characters and ﬁ gure, the more phosphor is
degraded. As shown in Fig. B, in case of displaying images that
have different brightness each for a long time, Fig. b shows that
the brighter image tends to obtain more remains.	[Fig. B]	[Fig. b]
	[Fig. B]	[Fig. b]

*The illustrations are images to explain the image retention. The actual manners on the image retention vary depending on such conditions as operation time and brightness.

Method to Reduce Image Retention

Use “Screen Wipe” or “Luminance Manager” function on the display, which are available from Function Menu. (Refer to 27 ~ 28 .)

After displaying certain images such as still image for a long time, “Screen Wipe” can be used to reduce the image retention by displaying a completely white screen for about 1~2 hours. In addition, “Luminance Manager” function works in case of displaying such images on the four corners as TV station logos and clock display.

Use in combination with moving images.

Since the entire screen has relatively even degradation of the phosphor in moving images, it can avoid the partial image retention. We recommend to use together with such moving images as DVD.

Please be careful that leaving the images in 2-picture mode for a long period of time can cause the image retention. Some television broadcasts contain images of which cut the left/right or top/bottom, and which broadcast station or clock is displayed for a long time at the same position. Please be aware that it may cause the image retention. Image retention can be reduced by “Eco Mode” in Function menu. 27

Common phenomena of Plasma Display Panel

The following are the common phenomena when operating Plasma Display Panel due to its structural reason. Please note that they are not malfunctions.

Residual image

When a still image or menu is displayed on the screen for a short time (about a minute) and then switches to another image, it may leave an “after-image” on the screen.

The residual image will disappear on its own.

Surface on Panel

The plasma panel displays images by generating discharges internally. This could raise the temperature of the display surface. In addition, do not impact strongly on the surface of panel because plasma panel is ﬁ ne-processing glass even though the panel strengthens by the front ﬁ lter made of tempered glass.

Defective Spots on Panel

The plasma display panel is manufactured with high-precision technology. However, there might be some spots that are not emitted, brighter than the others, or in different colors, etc.

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