Advances in laser and 3D technologies are allowing police to reconstruct entire crime scenes and pieces of evidence.

The technology is being used in the inquest into last year's Lindt Cafe siege in Sydney, and it is hoped that it will help in counter-terrorism activities.

Forensic crime scene officer Domenic Raneri says the days of measuring crime scenes with a piece of string are over.

"The laser sweeps out 270 degrees which means it's capturing everything except for a very small area immediately below the scanner," he said.

He said each scan takes about five minutes to complete.

"We can move through the crime scene taking these scans and overlaying them with photography to create a colour photo-realistic rendering of the environment," he said.

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"Once we go back to the office and we reconstruct the scene on the computer we can actually then look at the scene from a number of different angles.

"We can take a measurement from any point that we've captured in the scan and do a number of different types of analysis."

Hand-held scanners are also being used to get up close to capture higher resolution images of things like blood splatters.

"From that point you can then go on to measure the droplets and perform an analysis of the trajectory," Mr Raneri explained.

"The handheld scanner has a certified accuracy to about 0.1 of a millimetre.

"So we're starting to see this evidence reaching our courts and going through the process of admission into evidence."

Mr Raneri said police could also use 3D printers to recreate pieces of evidence, such as weapons, enabling them to be handled by a jury.

"For cases where there may be complex evidence that needs to be looked at in a very tangible way, some types of evidence can't actually be handled by a jury, so we might take that scan and data and then print a model of it," he said.

The Police Association's Scott Weber said the technology had been used to rebuild the entire Lindt Cafe in 3D, and would be key to the current inquest.

"All of a sudden we're back at the crime scene, where people were, where the projectiles where, looking at the explosions, looking at ballistics," he said.

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He said counter-terrorism police were keen to use the technology to map out potential targets.

"It means we have that diagram that we can go through training scenarios and be better prepared if an incident does occur," he said.

Police say there is no limit to what technology can do to fight crime, and the CSIRO has now started developing 3D scanning drones.

The CSIRO's Thomas Lowe said the technology would have a number of uses.

"It's sort of a multi-pronged approach. On the one hand, developing it for unmanned aerial vehicles for aerial mapping of areas," he said.

"We're also making use of it in real time, not only for autonomous navigation of aerial vehicles, but also to give you a three-dimensional map as you move around a building."