handgun lasers, why is the dot so small?

[brickeyee]

If you spread the beam (de-collimate) it is going to be dimmer right away (same power over a larger area)

If you used a larger laser the battery life would go down very rapidly if you want to maintain beam intensity.

Twice the diameter would need at least 4 times the power for the same intensity.

You will also quickly get into cooling issues with a larger size laser diode (further clobbering battery life if you need a thermoelectric cooler) and adding size for a heat sink.

[MLeake]

BGutzman, having been through several active duty training courses, and having shot with a lot of active duty guys... I don't really care what the average soldier uses, as the average soldier isn't a particularly impressive shot, combat veteran or not.

This is particularly true with handguns.

And while I see a lot of lasers currently in use, those are almost exclusively on rifles and SMGs. I see very, very few handgun lasers in active duty use; the only one I've seen carried by a non-SOF type was carried by a supply weenie.

I've done a fair amount of shooting with and without lasers on handguns. I generally also find that they slow me down. As mentioned in other threads, they can be useful for shooting from odd positions, or around a barrier; they are great dry-firing tools. But depending on the type, they introduce parallax in one axis (if centerline mounted) or two axes; and the dot may not be visible if the gun is raised to the normal position where sights would be used.

It's really a separate skill-set. I can shoot either way, and I still have a laser on one of my handguns. But for most circumstances, I'm better off using the iron sights on that gun.

Let's see your refutation.

[troy_mclure]

i dont really see a lazer as a daytime sight, so a bit dimmer, but wider aiming dot would work for me.

[robhof]

I have one on my M9 and practice with and without it on, however, my wife who only shoots 22's and only grudgingly goes to the range a few times a year, gets extreme pleasure putting 15 rds from my M9 in the black WITH the laser, without she's all over the target, lack of practice, but if a BG enters our house and she grabs the always loaded M9 and squeezes the grip, the BG will be lit up and if stupid, ventillated. Nothing beats training, but a laser is definitely better than a sharp stick.

[BGutzman]

The physics of how fast a laser works is the same as light being reflected off any object...

So what we are to believe is your eyes percieve the light of the laser in some method that is slower than the light being reflected from the target or the only alternative that I can think of is waffling even for a microsecond between the traditional pistol sights and the laser... How else can one account for this "delay"?

Im not going through all the things that need to happen to make a good shot but in a sort version:

Traditional sights - Line the Front and Rear Sight or if you wish just the front sight and engage the target.

Laser (done correctly) - No aligning other than putting the red dot in place and engaging.

or as a reasonable alternative

You use the same method as the traditional method because the sight and the laser are basically on the same point.

Now for the sake of arguement someone please point out where in this the delay comes in... I argue it is a training issue of waffling between then sight and the laser and it is a training issue not a functional issue of the laser...

Im open to debate but I just dont see one here....

[Frank Ettin]

Originally Posted by BGutzman

The physics of how fast a laser works is the same as light being reflected off any object...

....Now for the sake of arguement someone please point out where in this the delay comes in...

The delay has nothing to do with the speed of light. The delay comes from the difference between the time it takes to pick up the front sight in a flash sight picture and the time it takes to see and identify the laser dot on the target.

Of course, it helps to understand the concept of the flash sight picture -- as described by Gregory Morrison in The Modern Technique of the Pistol:

“...Sight-alignment is simply the proper alignment of the front sight with the rear sight. Sight-picture combines sight-alignment with superimposition upon a selected target. These basic principles common to all sighted fire are applied much differently, however, with the Modern Technique.

“The flash sight-picture involves a glimpse of the sight-picture sufficient to confirm alignment....The target shooter’s gaze at the front sight has proven inappropriate for the bulk of pistolfighting. However, the practical shooter must start at this level and work up to the flash, which becomes reflexive as motor skills are refined. With practice, a consistent firing platform and firing stroke align the sights effortlessly. This index to the target eventually becomes an instantaneous confirmation of the sight-picture.

“...Using the flash sight-picture programs the reflex of aligning the weapon’s sights with the target instantly....There is good reason for sights: one needs them to align the barrel with the target reliably....” (Morrison, Gregory, The Modern Technique of the Pistol, Gunsite Press, 1991, pp 87 - 88, emphasis added)

But, as noted, lasers can be useful, for example, in awkward shooting positions, especially those that preclude seeing the sights.

[dahermit]

Veering back on topic, one of the major advantages of a laser is that it has an unlimited focal length - the dot is in focus no matter the distance of the target from the emitter. While you can add a lens that will increase the size of the dot, it will only be in focus at a fixed distance. The more that you depart from that fixed distance, the blurrier the dot will be.

The laser light is collimated - essentially, all of the light is traveling in one exact direction with its wavefront aligned in one plane. If you disrupt that collimation with a focusing lens, then that planar wavefront only exists at a fixed point, which you see as a well-defined dot. At any other point, you get a fuzzy dot.

Want a bigger dot? You need a bigger laser. Sorry...

Basically this is true...however I am not sure that you are using the correct terms.
A standard incandescent flashlight (and almost all light), is incoherent light in that it spreads out in all directions from the source. The marvelous thing about laser (light amplified by stimulated energy radiation), is that it is coherent light, which means it travels in parallel waves from its source without spreading out or dispersing. That is why unlike a flashlight, or lighthouse, it does not need a lens to focus it. However, without a lens to change the focus the "red dot", can be no larger the size of the ruby rod (the original lasers used ruby rods) from which it emanates. To get a red dot that does not fade out (like incoherent light), or is as big as a tennis ball, the ruby rod would have to be the size of a tennis ball.
Note; Modern high energy lasers that can weld steel are no longer based on ruby rods (some are gas filled hollow glass tubes), and are are invisible.
As mentioned, if one desires a high energy laser weapon of large diameter, one must use a huge amount of energy and a large diameter tube, or resort to a lens to concentrate the beam and then end up with a focal distance. Where as if there were no focusing lens, just a huge powerful beam of coherent light, the beam would be deadly in space, to an indefinite distance. Inside of Earth's atmosphere, the beam would be dissipated somewhat by fog, impurities in the air, steam from boiling blood and tissues of the human targets, etc. Nice huh?

[Deja vu]

As far as this goes, I was discussing the subject with several instructors at Gunsite (two of whom were Range Masters). They had been trying out Crimson Trace lasers and putting them though the paces. They indeed found using the laser did slow them down.

Instructors at Gunsite are not your usual Tom, Dick and Harry. That will be obvious to anyone going to the Gunsite website and checking out the backgrounds of the instructors. So if they found lasers to be slower, their opinion is worth paying attention to.

They did find that lasers could be useful when shooting from awkward positions or making the most effective use of cover. And a laser is no substitute for basic marksmanship skills. If you jerk the trigger, you will miss -- whether using sights, a laser or any other method of indexing on target.

not defending lasers here:

but it could be due to lack of practice. I bet if those guys practiced as much with a laser as they do with there open sights the speed would be pretty comparable.

[Skadoosh]

Its actually not difficult for a manufacturer of a laser to add an expansion lens and can be done without adding significant bulk to the focusing aperture housing.

And I can see a very practical application for a dime, nickle or even a quarter-sized aiming dot in a self-defense type of situation.

I wonder if this idea has been kicked around by any of the major lasersight companies.

[Double Naught Spy]

The delay has nothing to do with the speed of light. The delay comes from the difference between the time it takes to pick up the front sight in a flash sight picture and the time it takes to see and identify the laser dot on the target.

Sometimes the delay is finding the laser dot because it isn't actually on the target where it is expected, then trying to march it over to the target and then trying to get it on the target where you want it, LOL.

[JohnKSa]

To respond to a few comments:

Modern laser sights use Laser LEDs and have to be collimated. The designer can adjust the lens system to obtain more or less any desired dot size over a fairly wide size range. I have a laser pointer with an adjustable focus and you can adjust the dot from a pinpoint to about 2 inches in size when aiming it at a target about a yard away. At about 6 yards you can adjust the dot to be about 2 feet across. There dot can certainly be larger than the size of the lens and can also be focused to be smaller than the output lens.

Light travels very fast. The time it takes for light to travel from a laser sight to a target 1000 yards away and back again is about 6 millionths of a second. It could make the round trip about 45,000 times during the time it takes to blink your eye.

Back to the original question.

Laser dots are small because output power is regulated in the interest of eye safety and that means that a laser can only put out a certain amount of light.

The smaller the dot the more intense it will be because you're focusing that limited energy into a smaller area. If you make the dot bigger you'll make the dot less intense by spreading the light energy over a larger area and that will mean it won't be visible in as wide a range of conditions as it would be with a smaller dot. With my laser pointer adjusted to maximum size, it gets hard to pick up the dot at just a few yards distance--even indoors on a reflective surface.

For maximum contrast/intensity you need a small dot.