Quality inspection of vehicle side mirrors using automated optical methods that can be implemented in industrial environments. Displacements or dimensions in the order of the wavelength of light can be measured using laser light and interferometric principles. Real-time recognition of pedestrians and other objects is a great challenge for image processing algorithms. Cryptographic keys can be distributed safely using quantum optical principles in optical fibers transmitting low intensity light. Holography can spectacularly supplement the presentation of museum pieces.