So ive been working on an LCD setup for a while and I have run into this interesting problem....When I power up my lcd it comes on for a second with the backlight, but after a few seconds the backlight turns off but the screen stays on and works perfectly (can tell if you shine a flashlight on it). Anybody experienced this or have any ideas for fixing it?
Hey AdmiralUD, I have your answer, only 6 months late! I had this same problem with the first LCD I deconstructed last night and assumed I had broken something. Tonight I took apart another one and had the same problem. In both cases I had only plugged in one of the rails, since the wires on the bottom one were too short. As an experiment I plugged them both in and it works! It appears if only one is plugged in it detects this and shuts itself down. I’ve had some success putting the top rail under the acrylic where it belongs, then letting the bottom rail rest loose below the panel facing up. As you can see from the photos I’ve been using a “clam shell” design, which accommodates short ribbon cables, but unfortunately means the screen is upside down. This is not an issue for me however since my graphics card allows rotation of the screen.
I’m brand new and have been reading as many posts about LCD FTIR setups as I can find. Preparing to start my own project:
I was wondering, isn’t Nima’s “side DI” essentially the same as a LLP setup? What would be the pros and cons comparing “side DI” to LLP?
What are the issues with occlusion when using a 2 to 4 laser LLP setup compared to a 2 to 4 sided LED “side DI” setup? I would assume that occlusion would less of a problem with the side DI method, but what do you all think are the pros/cons?
Yes, it bears many similarities to LLP. LLP lasers are definitely more dangerous than IR LEDs, so more safety precautions have to be taken with LLP. Lasers are also more expensive. Side DI, because it is a form of DI, can track fiducials, whereas LLP cannot. LLP seems to be on the whole, simpler, with fewer wires and such - just the 2-4 laser modules, compared to Side DI’s many LEDs.
If you put LEDs on all four sides of the LCD, then occlusion would be minimized, especially with LEDs closer together. Thats the good thing about FTIR - no occlusion. 1-2 lasers can cause occlusion, but if you have 4...then you should be pretty good. Take a look at AlexP’s setup - he doesn’t seem to have any such problems.
I think some of the terminology is getting a bit confused.
Side DI isn’t really Side DI anymore, it’s not really DI at all and its same as LLP, but instead uses LEDs and so we’re calling it LED-LP. Before we had the whole LLP name, we were referring to this as Side DI, but really that’s not a very proper name. This technique, LED-LP, cannot use fiducials (since the surface isn’t lit up) and it has very similar results as LLP, only the light plane is much thicker.
@ cerupcat
Ah, ok. About the fiducials - I was reading this post in this thread: http://nuigroup.com/forums/viewreply/6206/ - and that’s where I got the info that LED-LP would work with fiducials. So can you clarify- do fiducials work or not? my impression from that post is that, yes, they do work - sorry for the confusion.
LED-LP makes sense - LED light plane. can you please add it to your ‘getting started with multi touch’ post? that would be great.
I dont even have any IR leds yet… and I dont think Ill be getting any anytime soon…
Anyone wanna donate some extra LEDs??? =\
I work for a cable company and managed to get the guys in our stock room to set aside all the old returned remote controls for digital boxes.
Cracked them open and got a bunch of IR leds. Some remotes even had 2 in them.
- For free IR leds you might want to ask the shop or stock manager at your local cable company or even electronics shop and see if they can set aside any dead remotes for you for parts and stop by once a week and pick them up.
@ cerupcat
Ah, ok. About the fiducials - I was reading this post in this thread: http://nuigroup.com/forums/viewreply/6206/ - and that’s where I got the info that LED-LP would work with fiducials. So can you clarify- do fiducials work or not? my impression from that post is that, yes, they do work - sorry for the confusion.
LED-LP makes sense - LED light plane. can you please add it to your ‘getting started with multi touch’ post? that would be great.
thx
rbedi100
In that post he is using an active IR source as a fiducial, which is not the same as a passive fiducial that is used in DI. An active fiducial can be detected by any setup, but is not generally used because it is bulky (must contain leds and a powersorce) and not practical to attach to an object that will be placed on the MT table (such as a mobile phone). The typical fiducial (just a raised pattern) will not work for LED-LP, that type is only compadible with DI.
currently Im building a FTIR MT display using a LCD screen too.
After disassembling my LCD screen I had some problems to remove the electronics from the backside so that the screen is entirely transparent. Here is a picture with the problematic electronics:
I would fold the electronics at the left and bottom of the screen to the outside, so that they are not in the view of the webcam. But my problem is the red marked cable on the picture. It prevents me from moving the electronics.
Did someone have the same problem? Are there any solutions?
Are you sure its a FFC cable? There is another cable which looks similiar. Both have 30 pins. Here is a picture of the cable for which I need a replacement.
Another problem is, that its glued at one side.
Would you recommend to buy a 30pin cable with 0,5 mm Raster (I measured it) and to replace it with the old one like this?
