[[aim:]] visual field is the extent of side vision a person has when looking straight ahead. defects in the visual field reflect a problem in the visual pathway (structures starting from the eye and connecting all the way to the visual cortex in the brain). a device used to measure the visual field is called a perimeter and the procedure is called perimetry.perimetry serves as a useful non-invasive diagnostic tool not only to localize the disease of the visual pathway but also to quantify the visual field extent. the current clinical practice of perimetry requires feedback from the patient. therefore this paradigm makes it very challenging to estimate visual fields of infants and toddlers (aged 0 to 36 months). in addition no perimeters are commercially available for babies, not just in india, but elsewhere in the world. testing the visual fields is as important in infants as it is for adults as several diseases like glaucoma also affects them. early detection of visual field loss, besides being of diagnostic value, will also help in better medical management and/or rehabilitation for the child. a device that meets the clinical need for proper quantification of visual fields in infants will add more value to the existing clinical practices. this project addressed this clinical need and developed a robust low-cost perimeter for babies. [[methods:]] we built a hemispherical dome with mild steel rods assembled at 24 equidistant meridians (angular intervals of 15° in the azimuthal direction).the diameter of this frame was 120 cm diameter. the inner surface of each meridian was embedded with led(light emitting diode) strips to provide the visual stimulus. an infrared (ir) camera was mounted at the apex of the dome to monitor the head / eye movements of the infants. the infant will be placed in supine (sleeping) position under the dome on a cushioned bed such that the center of the ir camera will be aligned between the two eyes of the infant. two leds were placed close to the camera to serve as a central fixation target.the ir leds placed around the camera towards the infant provided the illumination source for the ir camera in the dark room testing conditions. an embedded board connected to the led strips helped to control the stimulus through a usb interface to a laptop that was operated by the examiner. an intuitive custom gui (graphical user interface) has been built for the examiner to present the stimulus (lighted leds) in the periphery at known visual angles.in the dark, the lighted leds attract the infant’s attention that prompts them to look at it. the examiner monitors the infant’s eye movements through the live video feed displayed on the laptop and registers the response when the infant makes an eye movement.this response gives both the extent of the visual field and the reaction time (how quickly the infant moved their eye/head soon after showing the stimulus). at the end of the testing, the examiner was provided with a recorded video of the complete test, a visual field isopter (polar plot) map and a text text file with reaction times. [[results:]] we initially pilot tested 5 infants with this device prototype to assess comfort and sought feedback from parents. parents’ reviews were positive. the instrument showed a potential to be a diagnostic tool for mapping visual fields in infants. we have been further successful in collecting data from 15 babies visiting our clinic at l v prasad eye institute (lvpei) with or without ailments. with all this pilot data we are now positioned to collect a larger normative database for this prototype. our device offers new and creative technology solutions in an area with an unmet medical need i.e. checking visual fields for babies. the major advantages of this device would be low cost,portability, safe and pleasing testing conditions and rapid estimation of gross visual fields. this device, “pediatric perimeter”, was developed for a population (children < 3 years of age) to which currently no such screening device is available.