Finding a Display You Can Read in the Sun?

max3000 asks: "I'm currently building an embedded device that will be used outdoors, and the technology is pretty much nailed down at this point, except the display. Quite honestly, I'm confused and lost in all the display technologies out there: LCD (TFT, passive/active, and so forth), ChLCD, OLED, FED, AMLCD, EL, electrophoretic, ePaper like eInk, and more (some of which may overlap). Can you help a confused, fellow reader? What I need is (apparently) fairly complicated: an outdoor, sunlight-readable (at-a-glance readable, not squint-your-eyes readable), VGA/SVGA display. The display should have a 4-6 inch diagonal, capable of displaying at least 16 color grayscale, and it should be based on a technology with a roadmap to color in 2-3 years time. If not driveable directly from a PC, the display should come with a development kit that is." What small displays are out there that can meet these specifications?

Comments

Ask Sharp

[Ant P.]

They made the Game Boy Advance LCD.

Re:Ask Sharp

[fbjon]

The GBA (SP) had a transflective TFT, and was perfectly readable in the brightest sunlight, but only when tilted towards the sun. Tilt it so the screen is in shadow, and you can't see anything, because the front-light is way too weak to compete with daytime ambient light. That's the real problem: either you turn your screen towards the sun all the time, or you put in a powerful enough light that can rival the ambient lighting, and speedily drain the batteries at the same time.

OLPC

[Anonymous Coward]

you might want to look at the OLPC http://laptop.org/

        * Liquid-crystal display: 7.5" Dual-mode TFT display
        * Viewing area: 152.4 mm × 114.3 mm
        * Resolution: 1200 (H) × 900 (V) resolution (200 DPI)
        * Mono display: High-resolution, reflective monochrome mode
        * Color display: Standard-resolution, quincunx-sampled, transmissive color mode
        * Special "DCON" chip, that enables deswizzling and anti-aliasing in color mode, while enabling the display to remain live with the processor suspended.

http://laptop.org/en/laptop/hardware/specs.shtml

OLPC's XO

[Adhemar]

I googled in my memory.

At last FOSDEM, Jim Gettys gave a presentation of the technical specs of OLPC's XO-1 machine. I remember I found the part about the low-voltage sunlight readable display particularly impressive for a $135 device.

OLPC XO-1 manifacturer Quanta announced selling a XO-like device on the open market later this year, at a price around $200. Presumably it will have a display of the same technology.

Simple: Transreflective

[evilviper]

The only existing screen technology that likely suits your needs is transreflective LCDs. They're widely available, so you shouldn't have an problems.

Display tech with potential, like e-Ink, just isn't there yet, and likely won't be for several years.

Of course, if you want to go crazy, you could always grab an old LCD, and mount it in an enclosure with a massively powerful backlight, and lots of airflow directed at the screen to keep the LCD from burning up.