Questions about a purely-ILED display

Very doubtful. You would want the cooling fan and 12" heat sinks on the back of your TV. You wouldn't want to lift it.

LEDs have heat problems and burn out when they do.

LCDs produce next to no heat and are very light and electrical energy efficient.

Take a look at any of the new LED "decorative lighting" bulbs. One little LED and a massive heat sink to keep it cool. More efficient than an incandescent but it's own heat will destroy it.

I?m thinking of a hypothetical monitor for a TV/computer. This display does not use plasma, LCD, or a backlight to any extent. Instead it relies purely on ILEDs for emission of light, colors, and images. As with most screens, each pixel contains a red, green, and blue subpixel. However, in this hypothetical monitor, each subpixel consists of a single ILED.

ILED = Inorganic Light Emitting Diode

Each pixel ? and its respective subpixels ? are as small as physically- possible given the state of today?s technology. The screen contains as many pixels per area physically-possible with today?s technology. These specs ensure that highest possible image resolution.

What would be the disadvantages of this purely-ILED monitor ? besides the cost?

Would refresh rate apply to this type of monitor? If so, what would be the maximum refresh-rate possible with this monitor?

I think this type of display is the most energy-efficient possible considering today?s technology. Am I right?

ILED kicks LCD?s butt anyday.

These so-called ?LED TVs? in the current market as simply LCDs with LED backlights. These evil marketers are so manipulative and the customers who fall for them are so unwise.

LCDs reek. When an LCD monitor is turned on, it required more watts to stay dark than to be bright. My hypothetical ILED monitor does the exact opposite and is more eco-friendly because it doesn?t waste energy using a backlight.

My ILED screen totally kills both plasma and LCD technology. ILED also is significantly more energy-efficient than OLED.

OLED = Organic Light Emitting Diode

Any chance of my theoretical ILED display appearing in department stores in the next year?

Thanks,

Green Xenon

y-

The technology for driving it wouldn't be to complicated. PWM the intensity. You would do that for linearity.That means the display won't be at full power all time. You would also scan the array. You weren't thinking of pure DC. That would take a lot of wiring.

Maybe 30 years ago. Modern LEDs may exceed 90 lumens per watt at high power and are well over 100 lumens per watt at low power. Junction temperatures are rated for operating at over 135C without damage. This is why modern LCD have LED backlights and why giant outdoor displays use RGB LEDs directly.

Christmas string LEDs are designed to have a high resistance so they can connect directly to unfiltered line power without burning out or flickering too badly.

The issue making ILEDs displays so expensive is that you can't build an RGB array on one wafer. Blue LEDs aren't even compatible with silicon. It's an expensive and error prone process of assembling a million discrete chips together.

The heat has to go somewhere and with that energy density it would be very hard to remove it from the substrate.

All LEDs destroy themselves quickly from heat if it is not removed and they produce a lot of heat as wasted energy.

LCDs sets are already developed using LED backlights for illumination are already becoming commonplace. Even at the 10-15% efficiency (85-90% of energy is lost as heat) LEDs are barely making the fluorecent mark for efficiency, especially in multicoloured units (white). The only trick is they can be dimmed, quickly and more linearly, than fluorescents for power conservation in flat panels displays.

I doubt you will ever see LEDs used in flat panel displays until the efficiency of LEDs increase by large magnitudes. Until then the heat needs to be produced where it can be safely removed.

Christmas string LEDs are designed to have a high resistance so they can connect directly to unfiltered line power without burning out or flickering too badly.

The issue making ILEDs displays so expensive is that you can't build an RGB array on one wafer. Blue LEDs aren't even compatible with silicon. It's an expensive and error prone process of assembling a million discrete chips together.

ey

All the LED TV's I tested lately are cooler than LCD's, especially plasma. You can feel the heat from a couple feet away from most screens.

greg

I had perceived that also but me thinks this is mainly due to dimming selective bulbs. This cannot be done with the previous fluorescent tubes. White LEDs are not more efficient than fluorescents. Coloured ones are as that is their native output. White LEDs are created from a second conversion process or mixed colours.

Plasma was a bitch for heat. LCD was much better and the LED backlit is slightly better yet. Now smaller individual areas are being selected for dimming during dark patches on lED backlit sets.

This was not the the OP's concern though.

greg

Ever see one of those roadside electronic billboards with a strikingly bright display? Many of them have too coarse resolution to do more than text and simple graphics. Some of them now have enough pixels to do fairly decent video. These are direct-view LED displays. it is mostly a matter of cost and manufacturing technology why they are not in home-size displays. LCDs are made by printing conductive patterns on two glass sheets and placing the liquid crystal material between them. No individual assembly required, just a very precise printing technology. There is no similar technology to print the LEDs onto a substrate with the interconnections, YET. Certainly, this is being worked on HARD, mostly with organic LED materials, as they would be more applicable to a printing-like process.

With conservative design, ILEDs should be QUITE durable in this application, you don't need to light up a whole room, just put an image on a screen. If LEDs can light up an LCD display, they can surely be used to directly display an image. Hell, I have a digital LED clock that has been running 24/7 for 30+ years, and shows no loss of light output.

Jon

That appears to be about 5 years out of date.

LXML-PWC2 : 104 lm/W at 2.25W or 135 lm/W at 1W

The color quality is bad for those, but no worse than high efficiency fluorescent. Better CRI is available at lower efficiencies, as it is with most types of lights.

You're thinking of Organic LEDs. They can be built as high density arrays but the efficiency is no better than LCD panels.

Live performances are using discrete LEDs now. Not pixelated signs, but brilliant HD video that puts a home TV to shame. The only problem is the mechanical complexity.

You aren't doing your math.

All LED bulbs produces a lot of heat that needs to be taken away. Even your latest 135 lm/W LED bulbs are still 95 % heat sink to attempt to stop them from burning themsleves out. LED bulbs are just not that efficient yet and probably never will be and they cannot handle their own heat. IN a cnetral backlight location this can be handled but spread over a flatscreen may make this an expensive and formidable task.

I can't find the figures online but even these exceptional, vapourware bulbs that may come out in white colours run 20% efficient. This means that 5 times the light output of the screen is produced in heat and needs to be removed or the LED burns out with shortened life and efficiiency drops badly. With fluorescents and incandescents and irridescent bulbs temperature is not as critical.

Need an efficiency chart for lumens / Watt input.

The whole thing sounds like a better and more efficient / brighter screen with better resolutions but our current technology doen't give enough excuse to make the jump from LCD. The presence of LED backlighting is a start and means they are trying.

LXML-PWC2 : 104 lm/W at 2.25W or 135 lm/W at 1W

The color quality is bad for those, but no worse than high efficiency fluorescent. Better CRI is available at lower efficiencies, as it is with most types of lights.

You're thinking of Organic LEDs. They can be built as high density arrays but the efficiency is no better than LCD panels.

Live performances are using discrete LEDs now. Not pixelated signs, but brilliant HD video that puts a home TV to shame. The only problem is the mechanical complexity.

The heat has to go somewhere and with that energy density it would be very hard to remove it from the substrate.

All LEDs destroy themselves quickly from heat if it is not removed and they produce a lot of heat as wasted energy.

LCDs sets are already developed using LED backlights for illumination are already becoming commonplace. Even at the 10-15% efficiency (85-90% of energy is lost as heat) LEDs are barely making the fluorecent mark for efficiency, especially in multicoloured units (white). The only trick is they can be dimmed, quickly and more linearly, than fluorescents for power conservation in flat panels displays.

I doubt you will ever see LEDs used in flat panel displays until the efficiency of LEDs increase by large magnitudes. Until then the heat needs to be produced where it can be safely removed.

Christmas string LEDs are designed to have a high resistance so they can connect directly to unfiltered line power without burning out or flickering too badly.

The issue making ILEDs displays so expensive is that you can't build an RGB array on one wafer. Blue LEDs aren't even compatible with silicon. It's an expensive and error prone process of assembling a million discrete chips together. I will not see posts or email from Google because I must filter them as spam

OK, you win. I can't argue if you can't do math, will not look at specifications, or go outdoors to see HD LED monitors in use.

LOL.

Finally!

Those outdoor ones are quite course LEDS and have lots of cooling available, including fans roaring in them.

I guess time will tell. I just doubt the manufacturers will take the jump as the advantages are not big enough...yet.