Archivo: BiodegradablePlasticUtensils1

Descripción: Knives, forks, and spoons made from a biodegradable starch-polyester material. The photo has been realized using the photoelasticity method, an experimental method which gets a fairly accurate picture of stress distribution even around abrupt discontinuities in a material. When a ray of plane polarised light is passed through a photoelastic material, it gets resolved along the two principal stress directions and each of these components experiences different refractive indices. The difference in the refractive indices leads to a relative phase retardation between the two component waves. The setup used to photograph this photo was probably composed of: A regular light source, with a quarter-wave plate installed to polarize the emerging light A regular photo camera, with a quarter-wave plate installed in front of the lens Light and camera being installed and oriented in the same direction, the two quarter-wave plates were turned with the polarizing axis in the same direction.
Título: BiodegradablePlasticUtensils1
Créditos: This image was released by the Agricultural Research Service, the research agency of the United States Department of Agriculture, with the ID k7245-1 (next).
Autor(a): Scott Bauer
Permiso: Esta imágen o archivo es una obra de un empleado del Departamento de Agricultura de los Estados Unidos, creó durante el curso de los obligaciones oficiales del empleado. Como una obra del Gobierno federal de los Estados Unidos, este imágen es en el dominio público.
Términos de Uso: Dominio Público
Licencia: Dominio Público
¿Se exige la atribución?: No