A handheld device designed to make an item look larger is typically a magnifying glass. It consists of a convex lens that enlarges the appearance of objects when viewed through it. Magnifying glasses are commonly used for close-up tasks such as reading fine print, examining small details, or studying insects. They are portable and easy to use, making them a popular tool for both hobbyists and professionals.
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It is a magnifying glass. A microscope is also used but is not technically hand-held and the majority of the time has more than one lens.
Magnifying glass
A magnifying glass is a hand-held instrument used to make an item look larger by magnifying its image when viewed through the lens.
Hand lens.
Hand lens
That sounds like a magnifying glass.
RFID (Radio Frequency Identification) typically consists of two main components: a tag and a reader. The tag is often a small, flat device, which can be as tiny as a grain of rice, and contains a microchip and an antenna. The reader is usually a larger device, often resembling a handheld scanner or a fixed installation, and emits radio waves to communicate with the tag. Together, they enable the wireless exchange of data for tracking or identification purposes.
magnifying glass
spy glass
You can look online and use them or you can buy them online or in a store
Binocular