Calibration of a Non-invasive Glucose Measurement Device and Assessment of Its Performance in the Hypoglycemic Range in Patients With Type 1 Diabetes

Inclusion Criteria: * Male and female subjects between 18 and 40 years of age. * Diagnosed with type 1 diabetes mellitus. * Uses an insulin pen or pump. * Hb1Ac \> 55 mmol/mol at baseline visit. * Skin phototype 1-4 according to Fitzpatrick skin tone scale. * Willing to perform a minimum of 8 finger sticks per day during the study for the home-based study and approximately 16 finger sticks for the in-clinic study days. * Willing to have a peripheral venous catheter inserted. * Willing to provide written signed and dated informed consent. Exclusion Criteria: * Breastfeeding, pregnant, attempting to conceive or not willing and able to practice birth control according to approved contraceptives from NCA during the study execution (applicable to female subjects only). * Subjects not able to understand and read Danish. * Inability to comply with the study procedures as described by the study protocol, according to the opinion of the investigator. * Subject is not able to hold hand/arm steadily (including tremors and Parkinson's Disease). * Reduced circulation in hand. "Allen's test" is used for assessing hand circulation to evaluate occurrence of reduced blood. * Extensive skin changes, tattoos or diseases on probe application site (thenar) that could interfere with the accuracy of the interstitial glucose measurements. * Known allergy to medical grade alcohol. * Having active cancer treatment and/or use tetracyclines and other medication / topical agents known to increase photosensitivity in skin. * Medical history or any condition that may, in the opinion of the Investigator, compromise the subject's ability to participate * Concomitant medical condition which could present a risk to the safety or welfare of the subject or study staff. * Diagnosed with cardiovascular diseases. * Subjects currently enrolled in another study. * Radiotherapy for the past six months.