läpinäinen

Läpinäinen is a Finnish adjective that translates to transparent or see-through in English. It describes a material or substance that allows light to pass through it in such a way that objects behind it can be distinctly seen. This is in contrast to translucent materials, which allow light to pass through but scatter it, making objects behind them appear blurry or indistinct, and opaque materials, which do not allow light to pass through at all.

Examples of läpinäinen materials include clear glass, pure water, and certain types of plastic films. The degree of transparency can vary. For instance, while a window pane is typically läpinäinen, heavily tinted glass might be considered less so, or even translucent depending on the context and the observer's perception. In scientific contexts, the term might be used more rigorously to describe the optical properties of a material.

The concept of being läpinäinen is important in various fields, from optics and material science to everyday life. In architecture, läpinäinen materials like glass are used for windows and facades to allow natural light to enter buildings and to provide views of the outside. In manufacturing, transparency is a key characteristic for products like lenses, screens, and packaging. The opposite of läpinäinen is usually referred to as läpinäkymätön, meaning opaque.