1/4″ Series Wide Angle Lenses are designed for 1/4 inch or smaller size sensor. They come in a variety of mount types such as M7, M8, M10 and M12. They feature small dimension and short TTL. For example, CH1940 has a TTL of mere 9.56mm, that means the distance from the surface of the image sensor to the top of the lens is only 9.56mm long, which makes it ideal for space limited applications. When used with 1/4’’ sensor, CH1940 covers a 135 degrees horizontal field of view. 1/4’’ wide angle lenses can be used for various of applications, like smart refrigerator. smart refrigerator include a barcode scanner or camera that was designed to help consumers track the consumption of the items within. Refrigerator lenses enable you to look inside your refrigerator from across the room or across town to take the guesswork out of meal preparation and shopping. To protect lenses from fog and scratch, some refrigerator lenses are coated on the lens surface and the protective glass. But sometime, the surface of the lenses are still covered with mist. On the basis of the above solution, ChuangAn added a set of 24-hour power-on resistance wires between the lens and the glass protector so that there will be no mist on the surface of the lens under any circumstances.