Door security system. Person swiping a radio frequency programmed key against a sensor. This scanner is being used to open the door at left. Each key has a radio frequency transmitter that produces radio waves,telling the scanner that the person holding the key should be granted access | |
Licence : | Droits gérés |
Crédit: | Science Photo Library / Public Health England |
Taille de l’image : | 3670 px × 2391 px |
Model Release : | Non requis |
Property Release : | Non requis |
Restrictions : | - |