Characterisation of Skin Microstructure Under Normal and Atrophied States

Inclusion Criteria: * Male or female aged ≥ 6 months old. * Volunteers understand the purpose, modalities, and potential risks of the study. * Volunteers are able to read and understand English. * Volunteers are willing to sign the informed consent. * \[Patient cohort only\] Patients diagnosed with AD and * A recent history of persistent signs (last flare ≥3 months) * Currently controlled signs (ISGA 0-1; clear-almost clear) * At least 3 months of TCS use (continuous or intermittent, over the last 6 months) Exclusion Criteria: * Participants with any of the following on the measurement skin site (acne, suntan, birthmarks, multiple nevi, tattoos, blemishes, or dense body hair that obstruct the test areas). * Visible signs of eczema/inflammation at the general measurement sites. Excluding sites of specific interest (SSI) which are imaged in addition to the general measurement sites. * Participants with a condition that in the opinion of the investigator contradicts participation in the study. \[Healthy cohort only\] Participants with a history of chronic skin conditions (except acne). * Participants who have used any medication that could interfere with the trial aim prior to the start of the study (baseline/visit 1). \[Healthy cohort only\] Use of TCS at any point during the 6 months before the clinical visit (except hydrocortisone use for ≤4 weeks outside the target areas of skin). * Use of any topical product on the measurement areas within 24 hours prior to the measurement visit (\>6 hours for patients with severe symptoms). * Volunteers currently participating in an interventional clinical trial. * Volunteers incapable of giving fully informed consent. * Volunteers judged by the PI to be inappropriate for the study.