They may not exactly be in the same league as James Bond or Batman, but modern police officers are using an increasingly impressive array of high-tech gear to fight crime.

The hit retro TV cop-show LIfe on Mars hit the nail on the head with its portrayal of Seventies policing as a creaking, lumbering technology-free monster.

Equally, the plods of 30 years ago might well feel they'd landed in a sci-fi movie if they saw some of the gizmos at the disposal of their early 21st-century counterparts.

Essex-based officers involved in Operation Effective - a blitz on railway crime - have been using small neoprene fingerless gloves, fitted with a mini-metal detector.

The small, silent device sets off a vibrating wrist alert when the scanner in the palm of the glove brushes across metal.

Half a dozen gloves were issued to officers travelling on the trains, allowing them to discretely scan travellers for metal weapons.

One officer even admitted to wearing the scanner under his usual regular-issue gloves - giving suspects no clue a gentle pat down would quickly and discreetly reveal more than they realised.

Essex Police also recently tried using PDAs - handheld computers - to speed up the crime reporting process and reduce paperwork for officers on patrol.

The eventual aim is for officers to be be able to send all the details from a crime scene directly to a central computer via a wireless connection to a mobile phone.

They would also be able to use the PDA to get information from the main computer on suspects, similar incidents or other useful data.

In Devon, Plymouth-based officers are well ahead of the game, using lipstick-tube-sized video cameras mounted on their heads.

Last month a woman pleaded guilty to six counts of assault, after her violent actions were caught on a policeman's head-cam - the first time such evidence had been used in court.

PC Olly Taylor, with the camera nestled just about his left ear, was able to film the scratches on the face and neck of the woman's victim, along with footage of her assault on four officers.

The cameras are also used at football matches and drinking hotspots and are worn openly, so members of the public know they are being filmed.

Back in London, Met officers are using small, hand-held thermal-imaging cameras, to spot cannabis growers using innocuous-looking homes and outbuildings as hothouses.

Recent raids in the London borough of Haringey turned up cannabis bushes, powerful lighting systems, air circulation units and water pumps - all shown up by heat-seeking cameras.

In Humberside, police have handed out state-of-the-art "invisible ink" to householders to mark valuable items.

Each bottle of SmartWater marker fluid has its own unique DNA-style chemical code, traceable to a specific address.

The force can then scan suspects' hands under ultraviolet light to see which stolen goods they have been handling.

Phillipa Deverson is the product and development manager for Niton Equipment, based in West Sussex, the UK's biggest supplier of law enforcement and security equipment.

She says officers on the ground are often more switched on to the use of technology than their superiors.

"Often officers make plain to their bosses their needs. We were the first firm to help supply female-specific stab vests and boots.

"The original men's stab vests leave vulnerable gaps when women wear them - the tailored versions are much safer.

"We get equipment from all over the world, but we also have our own research department - a bit like James Bond's Q division.

"Much of the equipment eventually used by police forces has already been tried out and used by the military or secret services.

"It's a highly competitive and thus very confidential business."