Development of a New Device and Method to Assess the Degree of Myopia and/or Astigmatism in Myopic People

Inclusion Criteria: * Volunteers, fluent in French, willing to follow the protocol, able to read and understand the information form and give free and informed consent * Aged between 18 and 39 years at the time of study inclusion * Wear corrective glasses * With an ophthalmologist's prescription for corrective eyewear less than 3 years old * Spherical error of each meridian within the range of \[-5.00 ; -0.50 D\] * Cylindrical defect included in interval \[-4.50 ; 0.00 D\] * Corrected monocular visual acuity ≤ 0.0 logMAR for distance vision (≥10/10) * French Social Security beneficiary Exclusion Criteria: General criteria for non-inclusion: * Essilor International employee * Pregnant, or breast-feeding women (Article L1121-5) * Persons deprived of their liberty by a judicial or administrative decision and persons hospitalized without consent under Articles L. 3212-1 and L. 3213-1 who are not covered by the provisions of Article L. 1121-8 and persons admitted to a health or social establishment for purposes other than research * Adults incapable or unable to express consent (Article L1121-8) * Participant included in another ongoing study or in a period of exclusion * All categories of persons particularly protected under French law are excluded from this research (Articles L1121-5 to L1121-9 of the French Public Health Code) * Amblyopia, strabismus, nystagmus * Wearing progressive lenses The following elements are considered based on the participant's declaration : * Declared cataract, Aphakia (without lens) or pseudophakia (with intraocular implant) * Ocular surgery (iridectomy, refractive surgery, corneal transplant) * Ocular trauma (corneal deformation, contusion, chemical burn, foreign body intrusion, perforation, orbital fracture, enucleation) * Severe ocular pathology, involving loss of visual field as in glaucoma or retinitis pigmentosa, involving loss of acuity and severe discomfort in dimly or brightly lit environments as in Age related macular degeneration (AMD) or overt and treated dry eye. * Systemic pathology affecting vision (diabetes, uncontrolled blood pressure, myasthenia gravis, etc.). * Medication that may affect vision or interfere with study measures (antidepressants, medication with atropine-like effects). * Declared neurological deficits, in particular a history of epileptic pathology or sensory-motor coordination disorders, vestibular or cerebellar pathology (e.g. balance disorders).