The present invention refers to a process for the preparation of photochromatic optical elements, and corresponding photochromatic optical elements. A conditional-access terminal device reads and decrypts an encrypted conditional-access program from a memory storage device at start-up, and executes conditional-access processing in conformity to the obtained conditional-access program. The system allows customers to create work orders for the vendors and allows the vendors access to the work orders to schedule work based thereon and to review all previously submitted work. The feedback includes defining a 100% load level associated with the MCPA and feeding back information proportional to the measured gain level. The color effect-providing pigment includes a pigment substrate and an inorganic coating.