Clinical Observational Study on Changes in Skin Physiological Parameters Following Ablative and Non-Ablative Fractional Laser Treatment at Different Doses

Inclusion Criteria: * Female Chinese study participants aged 18 to 60 years (inclusive). * Fitzpatrick skin phototypes III, IV, or V. * Willing to receive non-ablative fractional laser (M22) and ablative fractional laser (CO2) irradiation on the test sites during the study. * No primary or secondary lesions (such as scars, ulcers, vesicles, tattoos) on the test sites. * Has not participated in any other studies involving the test area (forearms) in the past 2 months. * Agrees not to use skin-whitening products on the test area during the study period. * In good general health at the time of the study. * Volunteers to participate and signs the informed consent form and photo release authorization. * Willing to comply with all requirements of the study. Exclusion Criteria: * Study participants with skin diseases or skin allergies in the test area. * Presence of moderate to severe inflammatory skin diseases (e.g., active eczema, acute photosensitive dermatitis, etc.) on the test sites within the past 4 weeks, or those who require treatment with oral or topical corticosteroids or immunosuppressants for skin conditions. * On the day of the visit, the investigator judges the presence of significant diffuse erythema, desquamation, or exudation in the test area that may significantly affect skin color measurement. * The investigator assesses that the participant is currently suffering from a stable or progressively worsening disease. * Participant is planning for pregnancy, is pre…