Some simple comparisons between laser and radar speedmeters
There is no doubt that there are circumstances in which a laser can be used to measure vehicle speeds where it would be impossible for a radar to be used. For instance on a motorway or in a dense stream of traffic. This is possible because a laser is able to pinpoint a specific vehicle by having a very narrow beamwidth. However, for every advantage there is often a corresponding disadvantage and in this case, because the laser beam is very narrow, it MUST be aimed with great accuracy or the vehicle will not be held in the beam and the reading will be lost. Easy to do if it is a vehicle approaching head-on down a straight road, but not so easy where the laser has to be panned to follow the vehicle, or the road is undulating.
To achieve this accuracy of aiming is difficult when the laser is hand held and with cold hands very difficult. The answer is of course to use a tripod, but then the user has to set it up and is then tied to the laser position. There is no longer the opportunity to quickly check a vehicle that suddenly appears to be speeding if the officer is engaged on other matters, nor is it feasible to quickly throw a laser in the back of a vehicle and give chase to an offender, nor even to leave the laser to assist the public for whatever reason. The user is tied to the spot on which the laser is set up unless there are two people operating the speed check, which is not a very efficient use of precious manpower.
Then there is the cost difference. For the price of an average laser it is possible to purchase three Speedars. This means that during speed campaigns or when monitoring complaint locations, far greater coverage can be obtained for the same equipment cost. Also where community policing is practiced, the low cost of a Speedar means that it is economically feasible for local stations to have their own set so that local complaints can be checked quickly to see if they warrant the attention of the traffic department.
Cost of ownership is another factor. Lasers must be treated with considerably more care than radar guns. If the optics of a laser are disturbed through rough handling or impact damage (being dropped in other words) then the repair costs are going to be high and the time it is out of service may be long bearing in mind that it will almost certainly have to be returned to the manufacturers in the USA for repair. Of course you may be lucky enough to be loaned a replacement unit whilst it is away!
Radars have served well for the past 15 or so years and although there has been an advance in other technologies over the years, it does not seem sensible to abandon a tried and useful system simply because there is a something new available. There has been an advance in radar technology as well. Now, with Speedar, it is for the first time possible to know which way a target vehicle is moving so that this radar can now be used with confidence on a road where there is opposing traffic flow. The operator is in no doubt as to which vehicle the radar is locked onto, and with the narrower beamwidth of the Speedar it will remain locked onto its target much longer in the presence of other vehicles.