Lenovo T43 Laptop Display dimming

Ummm... watch your attributions. I wrote the above.

True. All of them have a calibration knob, mostly to compensate for changes in ambient temperature.

Point it at a mirror and you get the temperature of whatever you see in the mirror, not the temperature of the mirror. Yes, emissivity matters.

Most of DVM's have thermocouple inputs. I got lucky and bought a large box of pre-made thermocouples, in a variety of packages. I use the tiny ones for spot temperatures. Still, it would be nice to have a non-contact method that works.

In the past, I was working on converting a supermarket laser scanner mechanism into a flying spot IR imager. I had something that sorta worked but the response time was so slow, that is was nearly useless. If I have time, I plan to continue as I now have a faster microbolometer.

The one's that I've seen have a calibration for emissivity. Temperature compensation is internal and fixed.

Depends on your definition of mirror. If it's a front-surface mirror, yes. IR doesn't go thru the glass very well. I just did the experiment with a standard back-surface mirror and a clear sheet of glass. Readings were similar and not anywhere near the temp of the light bulb I was using as a a test source.

Intermittently. When the video vanished, the image was just visible when looked at from the correct angle. Although I didn't bother to prove it, the broken conductor was presumably the one leading to the lamp. Breaks in other conductors would have different effects.

Sylvia.

Y're right. The antique design that I threw together didn't have AGC. Range was determined by knobs and trim pots.

The FLIR imagers that I sometimes borrow has manual adjustments for image temp range and emissivity as well automatic DDE (digital detail enhancement) also known as AGC. On the side or bottom of the screen, is a crude color to temp calibration strip.

One of the product features is that it's almost point and shoot, with all adjustments being automatic.

Try it with low-E window glass. It reflects IR from the surface coating.

I just tried the mirror and light bulb test. Your correct. It doesn't work. I do have a borosilicate glass SIR "hot mirror" that reflects IR, but that's cheating. I tried it on the bathroom mirror and it didn't reflect much heat. However, a polished piece of aluminum sheet metal reflects IR just fine.

Zero for three. I'm not doing too well today.

Argh... the rubber grips on my Craftsman IR thermometer are oozing oil, getting sticky, and slowly disintegrating. What else can go wrong?