can LED technology support 1mm resolution ?

[Luc Filion]

I'm working on a project for which I need to mount LED panels to
display still text. I am looking for a very high LED resolution,
something below 1mm dot pitch between each diode.

Unfortunately, I cannot find any LED-based product that can actually
handle such a high resolution (3mm dot pitch seems to be a standard on
the market). And even with chip-on-board (bonding the LED die on the
PCB), it seems that it is not possible to go that small.

Do you know LED that can be integrated that way (1mm pitch) or should
I look at other technologies (tech. I do not know about!).

Note : I know LCD is an option, unfortunately, the lifetime of a LCD
is rather low compared to LED (about 10 times less), so LCD is
ungladly not an avenue for this current project.

Thank you all!

Luc Filion

 

[Ian Stirling]

Luc Filion <filion@grm.polymtl.ca> wrote:

I'm working on a project for which I need to mount LED panels to
display still text. I am looking for a very high LED resolution,
something below 1mm dot pitch between each diode.

Unfortunately, I cannot find any LED-based product that can actually
handle such a high resolution (3mm dot pitch seems to be a standard on
the market). And even with chip-on-board (bonding the LED die on the
PCB), it seems that it is not possible to go that small.

Sure, it's possible.
The LED chips are significantly smaller than 1mm.
Wirebonding should be possible, though will be interesting to get the yield.

What size of display?
What for?

Do you know LED that can be integrated that way (1mm pitch) or should
I look at other technologies (tech. I do not know about!).

Note : I know LCD is an option, unfortunately, the lifetime of a LCD
is rather low compared to LED (about 10 times less), so LCD is
ungladly not an avenue for this current project.

 

[Costas Vlachos]

"Luc Filion" <filion@grm.polymtl.ca> wrote in message
news:a3bcb1a0.0311101147.5320578f@posting.google.com...

I'm working on a project for which I need to mount LED panels to
display still text. I am looking for a very high LED resolution,
something below 1mm dot pitch between each diode.

Unfortunately, I cannot find any LED-based product that can actually
handle such a high resolution (3mm dot pitch seems to be a standard on
the market). And even with chip-on-board (bonding the LED die on the
PCB), it seems that it is not possible to go that small.

Do you know LED that can be integrated that way (1mm pitch) or should
I look at other technologies (tech. I do not know about!).

Note : I know LCD is an option, unfortunately, the lifetime of a LCD
is rather low compared to LED (about 10 times less), so LCD is
ungladly not an avenue for this current project.

Thank you all!

Luc Filion

You might want to have a look at Planar's electroluminescent (EL) displays.
See the links below:

http://www.planar.com/
http://www.planar.com/Products/Embedded_Display_Sol/Custom_Family/

They are a bit on the expensive side, but they are excellent in terms of
visual clarity (they emit their own light, no viewing angle issues), and
long life (MTBF of 100,000 hours minimum). I have used their EL240.128.45
panel with built-in SED1335 controller and was *amazed* by the quality of
these displays. Much better than LCDs or VFDs. Have a look at the links
above.

cheers,
Costas

 

[onestone]

Can you comment on the need for such fine resolution? Unless these were
being viewed very closely you wouldn't notice a slight gap between
parts, in which case 0603's might work for you. I believe I have seen
0402 LEDs claimed somewhere, but can't recall where, perhaps In
Electronic Components mag from Asia. If you could handle 2mm x 1.25 the
'GODZILLA' LEds fromAgilent have an oval lense which tends to help blur
the gaps between them as well.

Al

Luc Filion wrote:

I'm working on a project for which I need to mount LED panels to
display still text. I am looking for a very high LED resolution,
something below 1mm dot pitch between each diode.

Unfortunately, I cannot find any LED-based product that can actually
handle such a high resolution (3mm dot pitch seems to be a standard on
the market). And even with chip-on-board (bonding the LED die on the
PCB), it seems that it is not possible to go that small.

Do you know LED that can be integrated that way (1mm pitch) or should
I look at other technologies (tech. I do not know about!).

Note : I know LCD is an option, unfortunately, the lifetime of a LCD
is rather low compared to LED (about 10 times less), so LCD is
ungladly not an avenue for this current project.

Thank you all!

Luc Filion

--
Please remove capitalised letters to reply
My apologies for the inconvenience
Blame it on the morons that spam the net

 

[Bob Masta]

On 10 Nov 2003 11:47:12 -0800, filion@grm.polymtl.ca (Luc Filion)
wrote:

I'm working on a project for which I need to mount LED panels to
display still text. I am looking for a very high LED resolution,
something below 1mm dot pitch between each diode.

Unfortunately, I cannot find any LED-based product that can actually
handle such a high resolution (3mm dot pitch seems to be a standard on
the market). And even with chip-on-board (bonding the LED die on the
PCB), it seems that it is not possible to go that small.

Do you know LED that can be integrated that way (1mm pitch) or should
I look at other technologies (tech. I do not know about!).

Note : I know LCD is an option, unfortunately, the lifetime of a LCD
is rather low compared to LED (about 10 times less), so LCD is
ungladly not an avenue for this current project.

Thank you all!

Luc Filion

Funny, I just read a letter in Physics Today that discusses
the early history of gallium phosphide LEDs, by one of the
inventors. According to the author, one of the first uses
was in a classified military project to put digital information
on the film used in Royal Air Force reconnaissance planes.
He says: "... the encapsulated lamps were 1/32 inch
(just under 1 mm) in diameter". That was back in the
early 1960's, so you can probably get them a lot smaller now.


Bob Masta
dqatechATdaqartaDOTcom

D A Q A R T A
Data AcQuisition And Real-Time Analysis
www.daqarta.com

 

[Dr Engelbert Buxbaum]

Luc Filion wrote:

I'm working on a project for which I need to mount LED panels to
display still text. I am looking for a very high LED resolution,
something below 1mm dot pitch between each diode.

Unfortunately, I cannot find any LED-based product that can actually
handle such a high resolution (3mm dot pitch seems to be a standard on
the market). And even with chip-on-board (bonding the LED die on the
PCB), it seems that it is not possible to go that small.

Checking my Conrad (www.conrad.de) catalogue I find LEDs in 1 x 1 mm in
red, green and yellow. So they are on the market.

 

[Parmin]

Dr Engelbert Buxbaum <engelbert_buxbaum@hotmail.com> while reading the
NewsGroups, picked his nose and bring out news:bpt3l6$56u$02$1@news.t-
online.com:

Luc Filion wrote:

I'm working on a project for which I need to mount LED panels to
display still text. I am looking for a very high LED resolution,
something below 1mm dot pitch between each diode.

Unfortunately, I cannot find any LED-based product that can actually
handle such a high resolution (3mm dot pitch seems to be a standard on
the market). And even with chip-on-board (bonding the LED die on the
PCB), it seems that it is not possible to go that small.

Checking my Conrad (www.conrad.de) catalogue I find LEDs in 1 x 1 mm in
red, green and yellow. So they are on the market.

Err, ever read about OLED? they are LEDs at something like .17mm pitch
screen. And they are full colour too.

Try OLED at google.

D.