Quick Question: reddish screen at boot problem?

[fb3]

Is this a known condition with a 650MHz T20 Type: 2647-21U:

when you first turn it on, the screen has a reddish tint to it. This lasts just a few seconds then the screen is fine.

Anyone know of this?

[beeblebrox]

The cold cathode tube has 3 spectra, which decay after a few years, leading to distortion in the emitted spectrum from the tube itself.
Red is dominant, with other spectra being diminished. After a few seconds the UV rays of the tube emit enough photons for blueish and greenish phosporous pigments to light up enough to produce whitish color.

Your problem is an aged CCR tube. You can buy that tube (2mm by 250mm) separately from eBay vendors and put it into the LCD.
However, if the problem occurs only during startup, then is it a real problem?
I don't think so. Wait a few more years before exchanging the tube.

Hope I could help

[fb3]

The cold cathode tube has 3 spectra, which decay after a few years, leading to distortion in the emitted spectrum from the tube itself.
Red is dominant, with other spectra being diminished. After a few seconds the UV rays of the tube emit enough photons for blueish and greenish phosporous pigments to light up enough to produce whitish color.

Your problem is an aged CCR tube. You can buy that tube (2mm by 250mm) separately from eBay vendors and put it into the LCD.
However, if the problem occurs only during startup, then is it a real problem?
I don't think so. Wait a few more years before exchanging the tube.

Hope I could help

Thanks--Actually this is VERY helpful. I appreciate the quick response. I'll stop worrying.

fb

[JHEM]

Thanks--Actually this is VERY helpful. I appreciate the quick response. I'll stop worrying.

I have a Thinkpad 600X that displays this same problem on BOOT, i.e. a reddish display that eventually corrects itself as the unit warms up, usually in less than a minute.

The unit has been doing this for at least four years, three years of which it was my younger daughter's daily driver in college and grad school!

I have new LCDs for these units and have always told myself that I'll swap the display when it finally fails, but it keeps on correcting itself once it warms up.

I would say that you're safe to quit worrying about it, and when it completely fails, which might be never, you can do something about it then.

Regards,

James

[thinkpadhk]

What??? LCD's have cathode tubes? That sounds fishy to me. CRT's use cathode ray tubes, but LCD's use a totally different technology. Liquid Crytstals.

[ian]

...and cold cathode tubes for the backlight