Light Touch Technology (LTT) announced on May 11 that it has secured ¥500 million (approximately $3 million) in a Series B extension round. The Japanese startup, which develops non-invasive blood glucose sensors, has not disclosed the total raised across the full Series B, but cumulative fundraising now stands at ¥1.2 billion (approximately $7.7 million).
The company was founded in 2017 by Koichi Yamakawa, a laser researcher at the National Institutes for Quantum Science and Technology (QST). LTT is headquartered in Osaka and maintains a laboratory at QST’s facility in Kizugawa, Kyoto Prefecture.
Inspired by a colleague’s child living with Type 1 diabetes
For people living with diabetes, one of the most persistent daily stresses is measuring blood glucose levels. Current standard practice typically requires self-administered fingerstick tests four to five times a day.
Yamakawa’s decision to found LTT traces back to a conversation with a colleague whose child had been diagnosed with Type 1 diabetes, an autoimmune disease. In an interview published on the Japan Finance Corporation website, Yamakawa recalled: “The blood glucose level can drop dangerously low, so even in the middle of the night they would wake the sleeping child—no matter how hard the child cried—to draw blood. I felt for both the child and the mother. And at the same time, I thought: surely a laser could measure this.”
Near-infrared light (NIR) is one technology that has attracted attention for medical measurement applications. However, NIR-based blood glucose measurement is susceptible to interference from substances other than glucose, limiting its accuracy. LTT instead uses mid-infrared light (MIR), which it directs at a fingertip; glucose levels are then calculated from the rate at which specific substances in the blood absorb the light.
LTT has already developed both a desktop and a mobile non-invasive sensor based on this technology. Regulatory approval as a medical device is still pending, but the system is designed so that a five-second fingertip contact with the sensor transmits the result directly to a smartphone.
Funds earmarked for performance trials and production technology development
The Series B extension round was led by Tamron, JMTC Capital (the corporate venture capital arm of Japan Material Technologies Corporation), Hiroshima Venture Capital, and BP Capital.
The proceeds will be directed primarily toward clinical performance trials for the sensor and the development of production technologies for mass manufacturing, with the aim of accelerating regulatory approval and commercialization.
LTT President Yamakawa commented: “Our mission is to make needle-free blood glucose monitoring the new normal. We are confident that our technology is indispensable to achieving that future. LTT will keep moving toward a world free from pain.”
