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 | |
Lizenzart: | Lizenzpflichtig |
Credit: | Science Photo Library / Public Health England |
Bildgröße: | 3670 px × 2391 px |
Modell-Rechte: | nicht erforderlich |
Eigentums-Rechte: | nicht erforderlich |
Restrictions: | - |