Diabetes is one of the very common and chronic diseases in the present world, which affects children and adults. Diabetes is characterized by hyperglycemia. Hence, diabetic patients need to precisely monitor their blood sugar level regularly a few times a day. Currently, the solutions for self-monitoring blood glucose are invasive (finger prick method, continuous glucose monitoring (CGM) using microneedle).The fully non-invasive CGM approaches still are in high demand.

The medical device is developed, ultimately, to continuously measure the blood glucose level from continuous in-vivo photoacoustic signal.

For this study, the goal is to check if the signal collected by the investigational device is relevant and exploitable in patients with type I diabetes.

The main task of participants is to wear the investigational device during one week.

Inclusion Criteria:

• patients with type I diabetes
• male and female patients aged 18 to 50 years
• wearing a FreeStyle Libre CGM and giving the access of collected data
• using insulin pump or insulin pen and giving the access of collected data
• willing to wear the investigational device continuously throughout the study (24h/24h)
• affiliated with French Social Security
• having signed the informed consent form

Exclusion Criteria:

• any skin disease (inflammatory diseases of skin, cancer of skin, infectious diseases of skin, change in skin color...)
• any serious disease that could interfere with the study
• body mass index (BMI) > 30kg/m2
• scars or tattoos on the upper side of the wrist wearing the investigational device
• who may have an allergy to one of the material used in the device
• who have magnetic resonance imagery (MRI), computed tomography (CT) scan or high frequency electrical heat (diathermy) treatment during the study
• persons mentioned in articles L1121-5 to L1121-9 of the public health code (Pregnancy or Lactation ; Females with childbearing potential, defined as a premenopausal female and not using an effective form of birth control*; Person deprived of liberty by judicial order ; Person under guardianship or curatorship ; Minors ; Adults who are incapable or unable to give their consent ; Cross-over situations)
• who would receive more than 4500 euros in compensation due to his or her participation in other research involving the human person in the 12 months preceding this study
• who, in the judgment of the investigator, are likely to be non-compliant or uncooperative during the study, or unable to cooperate because of language problem, poor mental development