Optical apparatus and instruments, namely, cameras; thermal cameras; infrared cameras; active imaging cameras using IR or laser illuminations; infrared [ cooled and ] un-cooled cameras; thermal imaging cameras; thermal imaging systems not for medical use; thermal imaging apparatus for mobile devices; thermal imaging apparatus for smartphones; integrated electro-optical observation systems comprising cameras, thermal imagers, thermal sensors, computers, transmitters, and fixed and mobile mountings for monitoring, detection, protection and security [; systems for detecting a heat source ] [ and directing a stream towards it, ], [, namely, a system for detecting fire ] [ and directing a stream of water or foam towards it, ] [ as well as a system for detecting an intruder ] [ and directing a non-lethal stream of water or gas towards it, ] [ comprising cameras ] [, computers, radio transmitters, radio receivers, water cannons, loudspeakers, software, gas nozzles and cylinders and a control center; ] [ apparatus for the detection of gas and hazardous material leaks, comprising thermal vision units, namely, thermal cameras, thermal sensors, thermal imagers, infrared cameras, alarms, software and hardware for detecting fire, gas leaks, hazardous material leaks; aerial remote fire detectors; electric sensors, namely, heat and gas sensors; enhanced vision systems comprising day and night sensors, day and night cameras, power sources, communication means, monitors and operating software for airborne and land applications for surveillance purposes ]