A University of Washington researcher is developing an app to let eaters quickly detect just how many calories are in a meal.
While diet guides often list how many calories are in a particular food item, that data isn't perfect -- apples, sandwiches and just about every thing else on an diner's plate come in different sizes and contain different amounts of energy.
UW professor Alexander Mamishev hopes to solve that problem with an ordinary smartphone equipped with a snap-on laser that gives the device the ability to take three-dimensional measurements.
With those measurements, a smartphone can more accurately assess how many calories are in a particular serving.
The device -- called the Dietary Data Recorder System -- can be used to scan a single item, or an entire meal all at once. It can even measure the amount of leftovers a diner leaves on a plate, subtracting that caloric amount from the original estimate.
Using the scanner takes some practice. A user needs to scan a food item carefully so that it can make an accurate calorie count.
Mamishev, who runs the Sensors, Energy and Automation Laboratory, said his own eating habits have changed as a result of testing the calorie counter.
UW already has a contract with a local company to produce the device when it's ready for the public.