This clinical study has been launched to compare the performances of two models of a non-invasive glucose monitoring device.

Subjects will be optical screened at baseline visit. Study comprises two in-clinic visits. Subjects will arrive in a fasting state and and oral glucose bolus will be administered.

Subjects will during each of two study days be subjected to optical readings on two different device prototypes. During each of the study days, FGM readings, capillary blood samples and arterialized venous blood samples will be collected.

Inclusion Criteria:

• Male and female subjects 18 years of age or older
• Diabetic type 1 patients
• Insulin pump users
• Skin phototype 1-4

Exclusion Criteria:

• For female participants: Pregnancy or subject is attempting to conceive or not willing and able to practice birth control during the study duration
• For female participants: Breastfeeding
• Subjects not able to understand and read Danish
• In Investigator's opinion, subject is not able to follow instructions as specified in the protocol
• Rejection by optical screenings
• Subjects not able to hold hand/arm steadily (including tremors and Parkinson's Disease)
• Diagnosed with reduced circulation
• Extensive skin changes, tattoos or diseases on probe application site
• Known allergy to medical grade alcohol
• Known allergy to adhesives
• Systemic or topical administration of glucocorticoids for the past 7 days
• Subjects undergoing dialysis treatment
• 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
• Subjects currently enrolled in another study