A surface with a highly reflective finish can be seen to have a deep reflection and a high reflective contrast. However, one that exhibits a slight “milky” finish, observed as a milky halo or bloom from a reflection on the surface, is said to be suffering from Haze; the word Haze, therefore, is used to describe this effect.
![Image showing deep reflection and high reflective contrast](https://www.rhopointinstruments.com/wp-content/uploads/2022/03/Window1.png)
![Image showing shallow reflection and low reflective contrast](https://www.rhopointinstruments.com/wp-content/uploads/2022/03/Window2.png)
Haze is caused by microscopic surface textures that diffuse light adjacent to the main specular component of reflected light. When viewing the reflection of a strong light source in a surface with high haze the image “blooms” and has a bright halo around it.
![Image showing reflection of strong light source in a surface with low haze](https://www.rhopointinstruments.com/wp-content/uploads/2022/03/Effect1.png)
![Image showing reflection of strong light source in a surface with high haze](https://www.rhopointinstruments.com/wp-content/uploads/2022/03/Effect2.png)
Surface haze can be problematic in many coatings applications including automotive manufacture, powder coatings and other high gloss coatings. It can be attributed to a number of causes including incompatible materials in a formulation, poor dispersion and problems encountered during drying/curing/stoving. Haze is an important measure for highly polished metals and is often associated with polishing marks and machining direction.