eternaLight (4 models)

eternaLight (various models), retail $(see below) (
Manufactured by Technology Associates (
Last updated: 11-19-06

LED Light

The eternaLight is a pager-sized, microprocessor controlled, 4-LED pocket flashlight. These electronic marvels come in five different types, so there's one to suit every lifestyle.
  • The Model 2 Classic is the original eternaLight, updated with modern LEDs and energy saving circuitry.
  • The Ergo is an update to the Classic, with a more ergonomic (easy to hold) shape and stylish appearance.
  • The Ergo Marine is for you boaters. It comes in international yellow, so if it goes over, it's easy to find in the water.
  • The Ergo XRay is a good looking light in a cool blue case; this one has an "always on" blue light hidden inside to make finding it in the dark easier.
  • Finally, the Rave'n is, for all practical purposes, the party animal of flashlights. This guy has four colored LEDs and a complete set of computer programming to make them do many of the same tricks the other eternaLight models can do, plus it has a few of its own tricks hiding up its sleeve. Because the Rave'n is so different, it will be reviewed on a seperate page.

Current suggested retail prices (as of early June 2001) are:

Model 2 Classic: $39.99
Model 3 Ergo: $59.99 $39.99
Model 3M Marine: $79.99 $54.99
Model 3X Ergo X-Ray: $69.99 $49.99
Model X1 Rave'n: $39.99

All come with a limited lifetime warranty that covers everything except batteries and intentional acts of violence towards the flashlight.

To use this light, just rip open the pack and start pushing buttons. :)
If you just need some light really quick, press the rightmost button on the unit, and you've got light. Press it again, and you've got dark. But that's just the beginning of things for this light. Short of writing an instructional manual here, I'll outline the functions for all of the white eternaLight models, and how to access them. When you use any of the extras, push the right button once to get the light burning first.

  1. Timer mode (One LED shuts off every 2.5 minutes until they're all off): Don't do anything after turning the light on.
  2. Dimmer mode: Press center button. The leftmost button then dims the LEDs, from full power all the way down to a single LED burning weakly. Steps through all 17 brightness levels, then repeats.
  3. Flasher mode: Press center button again. The leftmost button controls flash rate. Light flashes brightly at around 8 flashes per second (adjustable).
  4. Strobe mode: Press center button again. The leftmost button controls rate. Like flash mode, but faster and with shorter bursts. This mode can provide some interesting stop-action effects in low light.
  5. Dazzle mode: Press center button again. The LEDs sequence in a neat, attention-getting pattern.
  6. S.O.S. mode: Press center button again (you may need to press it twice to get out of "dazzle" mode): Causes the light to flash the international S.O.S. distress signal; 3 short flashes, a pause, 3 long flashes, another pause, and 3 short flashes. Repeats indefinitely until you change modes or turn off the light.
  7. Pulse mode: Press center button again. The light goes out now, but you can push the leftmost button to turn the light on and off again at will (momentary operation). Useful for signalling or when you just need light here and there and don't need to burn it continuously.
  8. Off: Press rightmost button. You can turn it off from any mode with the rightmost button.

This is the "control panel" of the Classic eternaLight.
The distortion is caused by my camera's lens, not by any fault of the light.

The eternaLight comes in five different "flavors" (the Model 2 'Classic', Ergo, Ergo Marine, XRay, and Rave'n), and some models have some different functions that will be detailed below.

Here is another light in which you need to unscrew the case to get at the batteries. Fortunately though, you won't have to do it very often, since the batteries can last an amazing 700 hours (!) in it. Many people can go for months between changes even with frequent use.

When it is time for a change, get out your 00 Phillips and unscrew the four* screws holding the case together. Gently pull the halves apart, and there are your batteries. Out with the old, and in with the new. Place new batteries in as indicated by the polarity markings embossed inside the light. Put the other half back on, being sure the rubber seal is still on there right (although it probably won't ever become dislodged anyway), and screw it back together.

To make the screws easier to drive in, squeeze the two halves of the light together at the corner you're working on.

* The Model 2 and Rave'n have two screws on the upper half of the case, and not four on the corners. The battery change procedure for these two models is detailed inside the leaflet that comes with the flashlight, and differs a bit from the Ergo models.

All three Ergo models appear to be very durable and well-constructed. They are equipped with thick rubber seals (like O-rings, but contoured to fit the shape of the eternaLight body and to surround the LEDs) and are held together with four Phillips screws. The bodies are contoured and shaped to better fit the hand, and have a substantial, beefy feel to them.

The Classic and Rave'n are built smaller, are not quite as rugged (but still tough), and aren't completely waterproof. These two models were built in what appear to be custom modified garage door opener cases; trimmed inside to fit the batteries & circuitry, and thankfully, professionally milled & labelled. Despite this horrible sounding description, these things are built much better than the Turbospyder, so you shouldn't have any problems with them.

An extra feature of the Ergo XRay is the nifty blue glow function called the NightBeacon.
You can set the internal blue LED to wink every two seconds or glow continuously anytime the flashlight is turned off. This helps you find the Ergo XRay at night, and some users (such as myself) will like this as a nice but not overly bright nightlight and will keep the XRay on their nightstand ready at a moment's notice.
Locating the Ergo XRay inside a purse or handbag in a dark restaraunt or theatre is also easy with the NightBeacon feature enabled.

These pictures clearly show the NightBeacon as a blue light coming from within the Ergo XRay.

To turn the NightBeacon on, press the Power button to turn the Ergo XRay on. Then press and hold the Adjust button and then push & release the Power button. The main LEDs will switch off at this point, and the NightBeacon will be active. From then on, the NightBeacon can be switched between blink or steady with a single push of the Adjust button anytime the eternaLight is off. To turn this feature completely off, such as for long-term storage, just repeat the turn-on procedure.
With the NightBeacon set to burn steadily, the batteries will last 1 to 2 years, and when the beacon is set to blink, 1.5 to 2.5 years.

All models feature a spillproof switch panel with three tactile dome switches covered by a fairly thick rubber membrane; and all but the Rave'n feature a set of four Nichia white LEDs protruding from the front.

LED Light
This is the "quick" water test... the good ol bathroom basin.

The Ergo Marine has lithium cells in it so it floats (it's the yellow one) while the other two with heavy alkalines sink, although barely. And when they hit bottom they aim straight up, so if it's on when you dump it, it'll be easy to see in the water. Of course, all three of these Ergo models float with lithium batteries installed, so if you intend to camp with one of these, load it with lithiums and it'll never give you that sinking feeling.
If any of the Ergo models become dirty, just hose them off or wash them in the sink with cool water and mild dishwashing liquid.

All are also dimmable, which is achieved by a method called "pulse width modulation" in which instead of keeping the LED on steadily, the circuit feeds pulses to it and then turns it off for a time. If this is done quickly enough, the LEDs will appear to the human eye to become dimmer. Towards the lower ranges though, a noticeable flicker starts to appear. When you are staring directly at the spot of light created by the eternaLight, this normally isn't objectionable, and only becomes very noticeable if you view it well off-axis.

LED Light
This is the beam profile from all three Ergo models & the Classic.
All white eternaLight models were found to be identical in brightness and beam width.
Measures 34,700mcd on a Meterman LM631 light meter.

Contour beam plot.

Spatial distribution curve.
Flashlight and camera were 24" from screen for both of these images.
Created using the ProMetric System from Radiant Imaging.
This is a representative sample of an eternaLight white LED model.

Spectrographic plot
Spectrometer plot of the LEDs in this flashlight.
The eternaLight Ergo was used for this test.

Spectrographic plot
Spectrometer plot of the LED in this flashlight.
The eternaLight X-Ray was used for this spectrographic analysis.
Ocean Optics USB2000 Spectrometer on loan from TWO-CUBED.

There are five models which will be tested (or in one case, retested). Some differ in mainly cosmetic matters, while others have totally different functions and different intended uses.
The Rave'n will be tested seperately, as it is so different from the other models..

UPDATE 04-24-01: When loaded with alkaline batteries, the Ergo models weigh approximately 4.75 ounces, but when lithiums are used, this drops to approximately 3.09 ounces. I tend to gravitate towards using the lighter flashlight - however since this is my own preference, your experience may vary.

UPDATE 04-24-01: Both the Ergo and the Ergo Marine are now being tested in the fishtank. Both of them will be left in the tank until the single LED on the lowest power setting extinguishes; they will then be disassembled and checked for leakage. The Marine is floating upside-down, so the control panel is immersed. The Ergo sank to the bottom and is facing LEDs up as I suspected it would.

UPDATE 05-13-01: Both of the eternaLights in the fishtank are unchanged... algae is beginning to grow on & around the glowing LED of the Ergo.

LED Light

UPDATE 12-17-03: Just out of curiosity, I grabbed my Ergo Xray (the kind without the magnet), turned it on, and placed it in front of the back tire of my electric wheelchair. Then I got in the chair (around 400lbs with me in it), throttled the chair up, and ran over the Ergo Xray frontward and then backward. I half expected the case to crack at very minimum, but I found NO damage when I examined the flashlight afterward. And it stayed on during this punishment.

Note: This test was done on a rug with a closed loop pile with a total depth of about 1/16" to 1/10", with no padding or backing of any type. The underlying material is hard linoleum tile.


Good brightness.
Easy to learn functions.
Fun to play with.
Long to very long battery life.
Cheap & common batteries.
Unique in the world of flashlights.
White LEDs never yellow with weakening batteries.
Switches slightly recessed to help prevent unwanted activation.
Allows you to "dial in" just the amount of light you need.

Floats (if lithium batteries are used)
Has a lanyard loop.
Ergo Marine comes in an easy-to-see color; Ergo XRay's NightBeacon makes the light easy to locate at night or in a handbag.

Stands up in two different positions (on its butt or on its side); this is useful for "candle" style illumination or for night reading
Accessories are available for different mounting options, such as on the brim of a hat or over a belt.
Smaller size and lighter weight makes it more comfortable in pants pocket. When used with lithium cells, this one should even fit comfortably in a shirt pocket.


Battery change requires a small Phillips screwdriver.
A bit expensive to replace if lost or stolen.

Won't stand up on end for "candle" usage.
LEDs are somewhat exposed and although protected to some degree by the curvature of the flashlight body, they can be damaged under some admittedly extreme circumstances.
Some people may find the flashlight a bit bulky or awkward to hold, at least initially; and it can feel a bit strange in pants pockets until you get used to the unique shape. Using lithium batteries can make the light more comfortable to hold for long-term usage; carry it in a coat pocket if it's too big for pants.

No built-in provision for attaching a lanyard.
Not waterproof or water resistant.
LEDs are exposed (more so than the Ergo models) and subject to damage if it falls face-first onto something hard like concrete or exposed rock.
Battery compartment lacks the usual springs; brass contacts are more fragile than springs and could wear out or deform with extreme abuse or carelessness.

MANUFACTURER: Technology Associates
PRODUCT TYPE: Handheld LED flashlight
No. OF LAMPS: 4 white
BEAM TYPE: Central hotspot w/soft falloff.
SWITCH TYPE: Membrane type switches on top of case
BATTERY: 3x AA cells
CURRENT CONSUMPTION: Unknown/unable to measure
WATER RESISTANT: Varies with model
ACCESSORIES: None that I'm aware of
WARRANTY: Limited lifetime


eternaLight Classic

eternaLight Ergo

eternaLight ErgoMarine

eternaLight Ergo Xray

eternaLight * WWW.TECHASS.COM

Do you manufacture or sell an LED flashlight, task light, utility light, or module of some kind? Want to see it tested by a real person, under real working conditions? Do you then want to see how your light did? If you have a sample available for this type of real-world, real-time testing, please contact me at

Please visit this web page for contact information.

Unsolicited flashlights appearing in the mail are welcome, and it will automatically be assumed that you sent it in order to have it tested and evaluated for this site.
Be sure to include contact info or your company website's URL so visitors here will know where to purchase your product.

WHITE 5500-6500K InGaN+phosphor 
ULTRAVIOLET 370-390nm GaN 
BLUE 430nm GaN+SiC
BLUE 450 and 473nm InGaN
BLUE Silicon Carbide
TURQUOISE 495-505nm InGaN
GREEN 525nm InGaN 
YELLOW-GREEN 555-575mn GaAsP & related
YELLOW 585-595nm
AMBER 595-605nm
ORANGE 605-620nm
ORANGISH-RED 620-635nm
RED 640-700nm
INFRARED 700-1300nm
True RGB Full Color LED
Spider (Pirrahna) LEDs
True violet (400-418nm) LEDs
Agilent Barracuda & Prometheus LEDs
Oddball & Miscellaneous LEDs
Programmable RGB LED modules / fixtures
Where to buy these LEDs 
Links to other LED-related websites
The World's First Virtual LED Museum
The Punishment Zone - Where Flashlights Go to Die
Legal horse puckey, etc.
LEDSaurus (on-site LED Mini Mart)

This page is a frame from a website.
If you arrived on this page through an outside link,you can get the "full meal deal" by clicking here.