PRS-T1 Touch screen fails in halogen light

[atze]

My PRS-T1 works as expected most of the time, but occasionally the touch screen stops responding, or I have to swipe 5-6 times before it goes to the next page.

I have noticed that every time it has that issue I am reading in halogen light.

Is this just coincidence or is this a know problem with IR touch screens and Halogen light?

[Ashjuk]

As far as I was aware the touch screen technology used on the T1 is similar to that used on the x50 range i.e. IR.

I have a 650 that I use every night in bed and the only light source is two halogen spots, and I've never had a problem with the touch screen.

Perhaps a clean around the bezel might help. I was getting some odd pop-ups when waking my 650 which was cured by lightly brushing around the screen edge.

[atze]

This is starting to bug me. Every time I sit in the coffee shop, or even in my armchair with the reading light on (both places with halogen light), I have to use the buttons.

The reader works fine outside and in fluorescent light, but as soon as I'm in halogen light the touch screen becomes unreliable, in some cases unusable

If no one else has this issue, then maybe there is something wrong with my unit.

I'll do some thorough testing on the weekend.

[vxf]

I don't have a T1 - but I believe the touchscreen technology on the 350 and 950 is the same. And I have no trouble in halogen light... nor, frankly, do I see why it should matter. Are you sure it's not some other type of issue?

Heat has created problems with my units before - and halogen lights could heat things up. But I don't see it heating up your reader to THAT extent. But you never know...

[atze]

Originally Posted by vxf

... nor, frankly, do I see why it should matter. Are you sure it's not some other type of issue?

I just experimented with this. I sat down in my armchair with the halogen light off, just the fluoro on and every single swipe worked. I then turned the halogen light on and swiping only worked intermittently. I turned the halogen light off and it worked perfectly again. I tried this several times with the same results.

I don't know why it should matter. The only thing I can think of is that the halogen light is emitting some light in the IR spectrum. This in turn may interfere with the photodetector.

Since other's don't have that issue, maybe it is just a faulty photodetector and I should get the unit replaced.

[mwerle]

The other possibility, although remote since you mentioned it happens under at least two different lights, is that it's an issue with the halogen lamps. A quick internet search showed that some can interfere with IR.
Are the lamps very close to you/the reader, for example?

[dwig]

Originally Posted by atze

...The only thing I can think of is that the halogen light is emitting some light in the IR spectrum...

Halogen lights emit more IR than visible light, as do conventional tungsten lamps. This is not the case with LED and fluorescent lamps, which is why they are more efficient, producing more visible light and less waste IR per watt consumed.

[carpetmojo]

I've gone the whole hog and tried 350, 650, and T1, at varying distances from the halogen light source, and had no problems at all - sounds like a faulty something or other.

[atze]

Originally Posted by mwerle

The other possibility, although remote since you mentioned it happens under at least two different lights, is that it's an issue with the halogen lamps. A quick internet search showed that some can interfere with IR.
Are the lamps very close to you/the reader, for example?

At home I'm about a metre away from the halogen light, it's a reading light after all.
When I sit in the coffee shop the light is about 2 - 3 metres above me. Actually there the touch screen does not work at all.

[atze]

Originally Posted by dwig

Halogen lights emit more IR than visible light, as do conventional tungsten lamps. This is not the case with LED and fluorescent lamps, which is why they are more efficient, producing more visible light and less waste IR per watt consumed.

The touch screen does not work at all in the coffee shop. Their lights are very bright, and maybe they are actually tungsten light. They certainly are not fluoro, LED or regular incandescent lights.

[atze]

Originally Posted by carpetmojo

... sounds like a faulty something or other.

Yep, I'm starting to believe that too. I'll take it back to the shop on the weekend to see if I can get a replacement.

[Shieko]

I actually have noticed the exact same phenomenon as you... Night and day difference when reading below my halogen lamp or turning it off... This isn't just in your head, and if it's a fault, its probably more widespread than we really know.

Almost feels like more of a quirk, as annoying as it can be. I probably wont return mine over this.

[DrMoze]

Originally Posted by atze

Yep, I'm starting to believe that too. I'll take it back to the shop on the weekend to see if I can get a replacement.

atze, the smaller button next to the Quote button is a multi-quote button. You can reply to multiple comments in a single message.

As for the halogen quirk, different halogen lights will emit differently, and they can interfere with ir receivers. Seems like the problematic lights are doing this, whereas some other halogens are more benign.

[vxf]

Wow, I have no idea. But I did try my 350 and 950 under different halogen lights and had no issues.

Sorry to hear about your problems. Hope it's just a faulty unit. SONY, despite a non-stellar reputation, is pretty good about replacing units, so you shouldn't have problems. Good luck.

[mwerle]

FWIW, I got my first instance of the auto-page-flip bug last night - and it occurred while reading under halogen lights! Could just be coincidence as I just upgraded to the latest FW, and I just started using swipes instead of the buttons, either of which could have been the cause. But definitely more testing required!