The Fluke 754 Documenting Process Calibrator-HART wide-screen LCD has dark letters and bright background for legibility.
Improved display technology is already showing up in the test tools that electronics technicians rely on. We’re not talking 3D—at least not yet—but the new displays promise to be clearer and easier to read, yet just as tough and long lasting as you expect from Fluke.
Like many engineering challenges, designing a display means striking the right balance among sometimes conflicting requirements. A larger display might be easier to read, but gobble too much power or make the tool too big or expensive. Some promising technologies, like electronic ink (electrophoretic ink or E Ink), excel in clarity but can’t refresh data as fast as Fluke users expect. Touch screens save time, but if you’re wearing gloves you can’t operate a touch screen.
Find the sweet spot—that’s the job for Fluke display expert Joseph Ferrante. When a new test tool is in the works, Ferrante sits down with the product planning team to scope out the basic requirements. Displays get hashed over in one-on-one needs reviews with users. And as Ferrante put it, “we’re constantly searching industry for new display technologies.”
Tough demands, across the spectrum
The more sophisticated the tool, the greater the demands on the display. A ScopeMeter® portable oscilloscope, for instance, must show several data streams or waveforms at once, and respond to changes in near real time. So its liquid crystal display (LCD) features 256 colors and a rapid refresh rate. A full-time backlight makes the display extra vivid. The 240x320-pixel “quarter VGA” display on the Fluke 289 Digital Multimeter can display test results in graph form. Advanced thermal imagers like the Fluke Ti32 go even farther, using a full VGA display (480x640 pixels) to show all the details in a scene, and rapid refresh rates to keep up as technicians pan across a test location.
Simpler instruments also put displays to the test. For a handheld digital multimeter, durability is a top priority. In meters that must survive an extreme drop test, like the Fluke 28 II Industrial Multimeter, the LCD is specially mounted to absorb the impact. LCDs are covered with tough polycarbonate, then bashed with a steel ball to prove a direct strike won’t damage the display. In field use, battery drain can be an issue, and displays are the meter’s biggest power users. That’s why LED backlights, a significant power draw, time out after two minutes to help maximize battery life.
And for test tools from simple to advanced, users expect long life from their Fluke investments. Ferrante said that’s why Fluke has steered away from organic light emitting diode (OLED) technology. It’s impressively bright and crisp, he said, but “because it’s organic, its operating life is limited. If you kept your meter for five years, one of the colors in that display would drop out.”
The search goes on. E Ink, the display technology used in e-readers like the Amazon Kindle, provides great contrast between dark letters and a light background, it’s legible indoors and out, and it’s easy on batteries. Ferrante checked that out too. But Fluke displays have to perform wherever technicians travel, winter or summer. The E Ink refresh rate at subfreezing temperatures was too slow to keep up with fast-changing electronic signals.
“Electronics technicians expect more,” Ferrante said. “They’ll be working with bigger numbers and higher accuracy. Some calibrators go out to seven places after the decimal point. We’re switching from vacuum fluorescents to full color. People expect that now. If they’re paying $40,000 for a high-end calibrator, we’re not going to give them a monochrome display.”
The recently introduced 9640A RF Reference Source and 1594A/1595A Super-Thermometers both feature full-color displays. The new Fluke 754 Documenting Process Calibrator-HART has a backlit full color display, but its wide-screen LCD uses only two colors: black and white. The result is blacker letters and a brighter background, for improved legibility.
LCD remains the optimum display for most Fluke instruments, but keep your eyes open for more developments in the near future. Ferrante said Fluke will soon have more new display ideas to show off.