The new Garmin Colorado and Magellan Triton series (and now the Garmin Oregon too) have higher resolution screens than anything we’ve seen before in handheld GPS receivers. But those gorgeous and detailed displays come at a cost. Many early adopters have been surprised by the decreased visibility of these units in their natural habitat — the great outdoors.
To understand what’s going on here, let’s take a brief look at the technology involved. Handheld units typically use thin film transistor (TFT) liquid crystal displays (LCDs). These TFTs use a polarizing filter that determines how light is used. There are three different TFT technologies that can be used in displays:
- Transmissive TFT – Uses backlighting to illuminate the display.
- Reflective TFT – Uses ambient light (e.g., sunlight) to illuminate the display.
- Transflective TFT – Has a mirror like surface that allows backlight to pass through, yet also has the ability to reflect ambient light.
If you guessed that handheld GPS receivers tend to utilize transflective TFT technology, give yourself a gold star.
The problem is the increased number of pixels per square inch in these new, high resolution, receivers. Basically, more pixels equals less reflectivity. I’m no expert in this technology, but a couple of folks have tried to address it over at Groundspeak in this thread on the Garmin Colorado backlight.
I wrote about visibility issues in my Magellan Triton 1500 review;
I found it usable under light canopy, but severely limited in the brightest conditions. Interestingly enough, my Garmin Colorado 300 is more legible in full sun than in cloudy conditions, though in general it seems to outperform the Triton screen (I hope to have a full review of the Colorado 300 posted in the near future). These companies may be using different transflective technologies; the Triton 1500’s performance is also impacted by the additional touch screen layer.
I asked Garmin about these issues and received this response…
“Our engineers pushed the limits of technology with the Colorado’s vivid 3-inch display, working to bring Garmin’s customers the best resolution and readability without conceding quality in either category,” said spokesman Jake Jacobson.
I don’t think this is a deal-killer on these units. Just don’t expect a super-bright screen in all conditions. Which is something you may have on your current GPS!