The aim of the study was to determine the physiological temporal visual field border, based on theoretical calculations and by perimetric examination itself. Materials and Methods: A perimetry test was performed on 15 healthy subjects -seven women (27-30 years old) and eight men (28-46 years old), all of whom had healthy eyes with a visual acuity value of 1.0. The visual field was evaluated using a Medmont M700 with nasal displacement of the fixation point of 40 degrees. In total, 179 examined points of visual field were included. The model of the entry of temporal rays into the eye was created on the basis of the measured biometric values of the eye and with the help of the AD systems AutoCad and SolidWorks. RayViz for SolidWorks was able to simulate the passage of light rays through the model. Results: The temporal part of the subjective visual field border was up to 110 degrees in all eyes. Modelling of the input rays based on geometric optics in one of the participants in the testing revealed a theoretical temporal boundary of the visual field of 102 degrees. Conclusion: Theoretical calculations of geometric optics have shown that the temporal boundary of the visual field reaches up to 102 degrees in a healthy individual. By perimetric examination, this limit reached 110 degrees.