Nano,

I wish you good luck in your search. I will point out for starters though that the X/Y resolution of your print depends on the Pixels Per Inch of your screen. Do not be fooled by @k, 4K, 8K, markings when it comes to large screens. Today the best possible screens are small smartphone or iPad screens. You would likely be best off watching for upcoming VR displays which share a common need with us looking at LCDs.

Every time I come across a a new screen I ask two questions
#1 IS there a matching Display Driver board we can source and
#2 What's the PPI? You can plug the info in here: DPI love ♥ Easily find the DPI/PPI of any screen

Keep us posted on your progress.

 

Now tell him about the Sharp 5.5" screen with 500+ ppi or the Sony Z5 Premium with over 800ppi

IMO larger screens just add more complexity and uncertainty today. We are not yet in a soace where working solutions are easily acheivable. The light source along for a TV sized display would cost a fortune.

I've stated before that my goal would be about an 8inch build volume with a PPI north of 230 or so to be worthwhile. Your mileage may vary.

 

evilc66, did you already try the 15.6" screen?

Got some daylight resin today in the color grey(it's more beige?). Tried it on a macbook pro mid-2015 retina display. It took about 2 minutes for the blobs of ~0.2mm before it started to cure a little bit. Brightness is 300cd/m2 900:1 contrast so pretty comparable.

I found a 400 nits panel in the same size(so it's 30% brighter) but I'm not sure what kind of brightness is needed for decent cure times.

 

I know the feeling

I wanted to buy this LCD, but I'm a bit hesitant to do so after the results with the macbook pro LCD.
Have you inspected the back of the LCD? I cannot find any detailed pictures but I'm wondering how difficult it would be to remove the aluminium backing, replace the LED-Strip with a high power royal-blue LED-Strip and then place it all back together.

 

So, the frame shouldn't be too hard to remove? Nice! Looking at the picture below I assumed an aluminum foil that's being hold together with the black(metal?) frame.

I wanted to make a very thin bottom. Adding an array of LED's for the full 15.6" you either need a large array of LED's or place it at a large distance and use frensnel lenses and diffusion foil. I really liked the idea to have everything compact like the photocentric LC10.

I can imagine that 3Watt(arbitrary number, don't know the real values) of royal-blue side-lit LED's is much more effective than 3Watt of white side-lit LED's.

The resin I tested is photocentric daylight hard grey.

 

@WirelessguyNY @evilc66

Thanks for aclaration, really now i see that this project with 50" will be not good, the xy resolution will be very poor, 0.288 are practically 0.3mm

On the past i was thinking about the laser solution, but i have a laser here and when we need engraving anything it takes a lot of time, need anything faster...

Think that i need will with anything smaller and try all first, this project is Too complicated for my low knowledge in the matter and I must learn a lot..

I have many answers, first how can calculate the xy final resolution from DPI? finally i found this one DPI Calculator / PPI Calculator, fantastic for me

Now, need know exactly what will be need, thinking on about the size, from 20 to 24" 4K will be from 0.115 to 0.1384mm rresolution on xy, suficient for me.....

The first problem is looking for the best option, monitor or tv, would like control it directly from a pc, tv have usb or hdmi, will be easy to control it directly form my laptop?

As @fantasy2 would like Adding an array of LED's , the resin to use will be form photocentric daylight.

Give me your opinion

Thanks for all friends

nano

 

I understood that UV light in time breaks down the LCD. Also, the color filters in the LCD panel are optimized for a certain spectrum of light.

See below illustration:


The peak transmission wavelength is around 450nm, 525nm and >600nm. If you use 405nm(optimal for UV resin), 60% of the light is blocked by the blue filter.
If you use 450nm LED's(royal blue), above 90% is transmitted. A little goes through the green filter as well. Of course, this panel is RGBW, increasing the efficiency a bit, but still you would have 2 pixels for 450nm transmitting light vs 1 pixel.

So it still makes much more sense to work with daylight resin, even if you go for a LED-array behind the LCD to decrease the cure time. 1.5Watt of side-lit royal blue would be as efficient as 3Watt of UV(with the chance of a short lifespan for the LCD). The phosphor layer in the white side-lit LED's filters the needed wavelength making it pseudo full-spectrum... Losing a lot of efficiency as well.

I'm still really curious to make my own LED-strip out of royal blue LED's. They're not hard to source and making a PCB that fit's is not that difficult.

 

Make an accurate XY stage and put a nano-DLP or LED projector on it. This way you can scan the full surface by moving the projector around

 

I did some calculations today on using a separate backlight panel.

If you go for 450nm standard SMD LED's, you get >4000 cd/m2 in a diameter of 300mm(about the size of the panel). This is 256 LED's spaced 19mm apart and at a 90mm distance from the LCD. What goes through will be a little bit more than 2/3th(white, blue and little bit of green and red pixel).

If you want the same intensity with UV 405nm, you need 70% more LED's to get the same intensity(only the white pixel and ~30% of blue will let it through the filter). This will increase the heat generation a lot.

So taking 4000 cd/m2, 30% passthrough is 1200 cd/m2 = 1200 lumen/m2. That's still quite a lot more than the LCD side-lit, but not much compared to a DLP beamer. Suppose you have a beamer of 1500 lumen on a print surface of 100x100mm this would translate to 150,000 lumen/m2.. No where comparable. A pico DLP is somewhere around 100 lumen but that's still 10k lumen/m2.


If we can assume curing time works linear and the LC10 from photocentric3D uses the ipad screen at 400cd/m2 with a cure time of 8 seconds per layer, this would mean that using the 450nm array you need 0.8 seconds to cure, quite acceptable!

 

It does sound doable with these numbers.
If you have plenty of light available, I'm thinking about adding a 4mm glass sheet behind the LCD panel so it will be much less fragile and you can make a very nice solid frame with it so you won't damage the LCD when placing the tray with resin on top of it.

 

The glass think is a good idea, but what about a good refrigeration?? If we put a couple of good fans, would help to cool the heat produced by the LEDs, could it work?

 

@ evilc66, i see on the net a 3d printer named slash, here are the tecnical especifications....

SLASH
Printing
Printing Technology
LCD Stereolithography
Separation Mechanism
Natural peel with special engineered polymer film
Up to 100x more durable than PDMS
Build Volume
192 × 122 × 200mm
7.5" × 4.8" × 7.8"
XY Resolution
75µm, WQXGA [2560 × 1600]
Layer Thickness (Z resolution)
10, 25, 50, 100, 200, 300 microns
Variable and customizable
Supporting
Uniz Smart support technology
Automatically generated
Manual add, adjust and remove
Printing Speed
1000 cc/hr (50% infill solid structures)
Up to 200mm/hr (hollow and thin-wall structures)
Resin Level Control
Automatic level control on bottle and resin tank
Unattended printing possible
Auto pause when resin runs out
One-Click Printing
Yes
Hardware
Dimension
350 × 400 × 530mm [W×H×D]
14" × 16" × 21"
Weight
12KG/26LB
Operating Temperature
Suggested 18-28°C
Suggested 64-82°F
Power Requirement
100-240VAC
12A 50/60Hz
240W
Optical System
5000 Lux blue LED array
Refractive index matched liquid cooling
Ultra high resolution LCD
Chassis
Injection molded, fully enclosed
Connectivity
USB, Wifi
Package Weight
14KG/31LB
Packaging Dimension
400 × 500 × 600mm [W×H×D]
16" × 20" × 24"
Materials
Packaging
500mL bottle
zABS Resin
ABS like, varies colors available
Desktop Software
System Requirement
Windows 7 and up
Mac OS X 10.8 and up
OpenGL 2.1
2GB RAM
Features
Simple print setup, easy multi-printer management
Z resolution profile customization from 10 to 300µm
Auto-generation of supportrs
Manual add, adjust, and removal of supportrs
Rotation, scaling and duplication
Compatible Format
.STL, .OBJ, .UNIZ
Mobile Apps
Compatible Systems
iPhone
iPad
Android phone
Features
Pre-validated online model store
One-click printing
On-the-go print monitoring and management
In-App purchases

 

Take atention on this one:

Optical System
5000 Lux blue LED array
Refractive index matched liquid cooling

Build Volume
192 × 122 × 200mm
7.5" × 4.8" × 7.8"
XY Resolution
75µm, WQXGA [2560 × 1600]

Perhaps this could help us, dont know exactly the LCD installed on the printer, but they are selling it for 190~$

 

So these from Ali would work without modification? Place under flexvat type and it will cure resin properly? The longer I've watched these threads for the last year the more I've wanted to dive in.

 

@ evilc66 Like I said, I do not have much idea of all this type of systems, but to stubborn one nobody gains me, jajajjaja

Me spends trying to find and looking for the best systems....

Now is your time, try to find any similar for my project, around 24"

 

Now, i need start with mine, as i need anything big, if i cant give more xy space will want more on z axis, i will need help and info about stepers and screw, if i supose a z axis around 50cm, perhaps a max weigth of piece around 20kg, and a good possible resolution, from 0.04to 0.1 configurable.

Culd give me any help here???

 

So, have you printed anything with this yet? Not sure what you got the HDX screen for but the screen vat and build area are on slash3d's sites.