Imaging and Spectral Analysis of the Crystalline Lens Using the "HYPERLAF" Slit Lamp

• Non-contact observation of the crystalline lens nucleus (Diagnostic test): Non-contact observation of the crystalline lens nucleus with a modified slit lamp combining an imaging system and a spectral measurement.

Primary outcomes

• Reproducibility of COLOR score measurement. [at inclusion, This is a one-day study.]: To assess the reproducibility of the COLOR score measurement, we will perform three consecutive measurements for each lens in each subject. In practice, the measurement procedure will be repeated from the beginning: for each measurement, the patient will sit on the LAF, the observer will focus the light on the lens, take the measurement, and then move on to the other eye. At the end, the patient will step back. Reproducibility will be quantified using the intraclass correlation coefficient (ICC).

Secondary outcomes

• Reproducibility of OPAK score [at inclusion, This is a one-day study.]: To assess the reproducibility of the OPAK score measurement, we will perform three consecutive measurements for each lens in each subject. In practice, the measurement procedure will be repeated from the beginning: for each measurement, the patient will sit on the LAF, the observer will focus the light on the lens, take the measurement, and then move on to the other eye. At the end, the patient will step back. Reproducibility will be quantified using the intraclass correlation coefficient (ICC).
• Distribution of the COLOR score in the study population [at inclusion, This is a one-day study.]: The COLOR score values measured in the study population will be described using appropriate descriptive statistics, including distribution, variability, and minimum and maximum values.
• Distribution of the OPAK score in the study population [at inclusion, this is a one-day study]: The OPAK score values measured in the study population will be described using appropriate descriptive statistics, including distribution, variability, and minimum and maximum values.
• Association between the COLOR score and LOCS III components [at inclusion, This is a one-day study.]: The association between the COLOR score and the individual components of the LOCS III (Lens Opacities Classification System III) score will be analyzed using appropriate statistical methods. LOCS III components will be assessed from digital lens photographs obtained using the LAF as part of routine care in the Ophthalmology Department of Saint-Etienne University Hospital.
• Association between the OPAK score and LOCS III components [at inclusion, this is a one-day study]: The association between the OPAK score and the individual components of the LOCS III score will be analyzed using appropriate statistical methods. LOCS III components will be assessed from digital lens photographs obtained using the LAF as part of routine care in the Ophthalmology Department of Saint-Etienne University Hospital.
• Proportion of usable device measurements [At inclusion, This is a one-day study.]: The feasibility of device measurements will be assessed by calculating the proportion of attempted measurements that yield usable results. The numerator will be the number of usable measurements and the denominator will be the total number of attempted measurements.
• Frequency of technical difficulties during device measurements [at inclusion, this is a one-day study]: Technical difficulties encountered during device use will be recorded, including difficulties with device alignment and measurement acquisition. The number and nature of these difficulties will be described.
• Duration of the device examination [at inclusion, this is a one-day study]: The time required to perform the device examination will be recorded in minutes for each subject. The examination duration will be summarized using appropriate descriptive statistics.

Sex: All, ages: 18 Years to any

Inclusion Criteria :

* Patients enrolled in or eligible for a social security program
* Age 18 or older
* Patients with cataracts. In cases of bilateral cataracts, both eyes will be photographed and analyzed.
* Patient who has already received an instillation of 0.5% mydriaticum (tropicamide) and 10% neosynephrine (Théa Laboratories, Clermont-Ferrand, France) eye drops to dilate the pupil of the eye to be photographed (or both eyes).
* Signature of the consent form

Exclusion Criteria :

* Severe blepharospasm making the examination impossible.
* Poor or absent pupil dilation: patient with an allergy or intolerance to the eye drops used for pupil dilation; refusal of pupil dilation during the eye examination.
* Pregnant or breastfeeding patient
* person under legal guardianship