The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the inventive concepts. As used herein, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It should be further understood that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

FIG. 1 is a diagram illustrating a wearable device 100 that performs various functions through vein authentication, according to an exemplary embodiment.

The wearable device 100 may include a sensor 110 and a display unit 120 (e.g., display). The sensor 110 may perform a variety of functions such as capturing a vein image of a user or sensing a body temperature of the user. The display unit 120 may display at least one of an image, an icon, a clock, a video, etc.

The wearable device 100 may capture an image of the veins of the user to acquire the vein image. The wearable device 100 may capture the vein image in response to a predetermined situation occurring. For example, the wearable device 100 may sense a particular situation, such as a user putting on or taking off the wearable device 100, a user's performing a particular operation, a specific function being executed, or a particular application being executed, etc.