Thermal binoculars / InfiRayDiscontinued
InfiRay Gemini GEH50R
640×512 · 50 mm · Not sold through US dealers
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Ground across the screen at 100 yd
Field width
How many feet of ground fill the screen at 100 yards. Wider makes scanning faster; narrower usually means more detail on the animal.
46 ft
Wider than 35% of the 40 current thermal binoculars we track (tied for #18).
Specs
| Sensor | |
|---|---|
| Resolution Sensor resolution How many heat-reading pixels the sensor has, such as 384 × 288 or 640 × 512. More pixels show more detail, but the lens matters just as much. | 640 × 512 |
| Pixel pitch Pixel pitch The size of each sensor pixel, in microns. Smaller pixels mean more magnification from the same lens. Most current thermals use 12 microns. | Not published |
| NETD (maker’s claim) NETD (thermal sensitivity) How small a temperature difference the sensor can show. Lower is better, but brands measure it differently, so numbers from two makers are not a fair comparison. | <25 mK |
| Refresh rate Refresh rate How many times per second the picture updates. 50 or 60 times a second looks smooth; lower rates stutter when you pan or a coyote runs. | Not published |
| Optics | |
| Lens Focal length The lens number in millimeters, like 35 mm or 50 mm. A longer lens puts more pixels on a distant animal but shows a narrower slice of ground. | 50 mm |
| Base magnification Base magnification How much bigger things look before any digital zoom, like 2× or 4×. Higher is not automatically better: it narrows your view. | 4.1× |
| Max digital zoom Digital zoom Electronic enlarging of the picture. It makes the animal look bigger but adds no detail; past about 2× to 4× the image gets blocky. | 16.4× |
| Field of view Field of view How wide a view you get, in degrees. A wide view makes scanning for animals faster; a narrow one usually means more magnification. | 8.8° × 6.6°Thermal channel figures. Digital channel: 1920x1080, 35 mm, 9.4° x 7.0°, 3.8-15.2x. Two 1024x768 AMOLED displays. |
| Detection range (maker’s claim) Detection range The maker's figure for how far away a warm object shows up as a dot or two. It is far longer than the distance you can tell what the animal is. | 2,843 yd |
| Display | |
| Display Display resolution How many pixels the small screen inside the eyepiece has. A sharp screen looks cleaner but cannot add detail the sensor did not capture. | AMOLED 1024 × 768 |
| Power | |
| Battery | 18650 cells x2, 3.2 Ah, removable |
| Runtime Battery life (runtime) How many hours the device runs on a charge, by the maker's test. Real runtime is shorter in the cold and with Wi-Fi, recording or the rangefinder on. | Not published |
| Features | |
| Rangefinder Laser rangefinder A built-in laser that measures how far away the animal is. The rated range is for big, reflective targets; expect much less on a coyote. | 1,312 yd |
| Storage Onboard recording (storage) Built-in memory that records photos and video of what you see. Useful for reviewing shots and sharing hunts; listed in gigabytes. | — |
| Wi-Fi / app Wi-Fi and app A wireless link to a phone app for live viewing, downloading videos, changing settings and updating the device's software. | — |
| Build | |
| Weight Weight How heavy the device is. Check whether the maker weighed it with or without the battery, because brands do it differently. | 33.9 oz |
| Water rating IP rating (water rating) A two-part code for how well the device keeps out dust and water. IP67 means dust-tight and survives a short dunk; an X means not tested. | Not rated |
| Operating temp Operating temperature The temperature range the maker says the device will work in. Batteries lose much of their runtime well before the low end of that range. | Not published |
| Buying | |
| Warranty Warranty How long the maker promises to repair or replace a faulty unit. Check whether it needs registration and whether it passes to a second owner. | Not published for US |
| US price US price The price we found for the unit in the US, with where it came from and when. Prices change often, so treat it as a snapshot. | Not sold through US dealers |
| MSRP MSRP The maker's suggested retail price in the US: the list price, before any sale. Useful for seeing how good a deal really is. | Not sold through US dealers |
Source: InfiRay Outdoor Gemini product page (infirayoutdoor.com).
Added October 11, 2026 · Specs last checked October 11, 2026