Lasever LSR473ML-100 DPSS laser review

[LaserLover]

I finally picked up my Blue laser today at Fedex. Tks David Wu @ Lasever.

I unpacked unit and was surprised that they sent me a pair of finned heatsinks with the laser.
You get 2 heatsinks, one power pack, a laser power supply and the laser head.

I quickly read the instructions and mounted both the laser head and the power supply to the heatsinks provided.

I have a digital laser power meter and also a digital temperature meter with multiple probes.
I attached one probe to the heatsink for the power supply and one to the top of the laser head.
I setup my laser power meter with sensor at slight angle to reduce any reflection back into the laser cavity.

I fired up the laser and started taking readings and making observations.
The power supply has a built in delay of 6 seconds before it starts and appears to ramp up power gradually.
I observed TEM 01 Initially which stabilised to TEM 00 after about 10 seconds and the laser output had shot up to 138 milliwatts (head and power supply temp started at 16 degrees Celsius). After about 20 minutes the laser head was at 20 C and power supply at 24 C. The laser power reading was 110 milliwatts.

I decided to add 2 cooling fans ( 4 inch muffins salvaged from PC power supplies) to cool down both the power supply and the laser head. After 20 minutes warmup it stabilsed at 120 milliwatts and both the laser head and pwr supply measured 20 C. You really need active cooling on this unit if you want more power and longer lifetime so i think they should recomend cooling fans.
A weak point seemed to be the power pack to Laser power supply connection. the cheap connectors and poor mating between plug and jack seemed flimsy and certainly a point of failure . Definitely not a solid connection prone to oxidation and stress induced from current flow and mechanical failure over time.

I've yet to test this using a TEC cooler to see If I can maintain 16 degrees C and raise the power to 140 milliwatts but that's next.
I also haven't tested the analog modulation but that won't come until i integrate it into my projector to complete RGB full color at around 750 millliwatts white light total output.
Beam shape is slightly rectangular as opposed to circular but i haven't tried adjusting the optics yet to optimise the spot size.
I'm happy with it so far.

Rick

[allthatwhichis]

Sounds nice. Toss some pictures up here. I;d like to see your cooling methods...

[dave]

the laser has a tec inside, so going overboard on cooling will have small effect at best..

Dave

[LaserLover]

the laser has a tec inside, so going overboard on cooling will have small effect at best..

Dave

Well as I mentioned going from passive heatsink cooling only to active fan cooling brought the stabilised power level up from 110 mW to 120 mW so I wouldn't call 10 milliwatts a small effect but a nice little boost in power.
More testing results to follow when time allows. I will try using Lithium heatsink grease to increase the thermal transfer to the heatsinks for starters and then fan cool both the pwr supply and the laser head to see If any improvements can be measured. I will then try an external TEC on the laser head heatsink so see if I can dissipate more heat and boost the laser output power. Note at 16 degrees Celsius the power was 138 mW.
I would say that the internal TEC is underrated or not driven sufficiently to provide adequate cooling for long timeframes.

Rick

[MechEng3]

I have set the PID controller to 25 deg C. I was warned about frost building inside the laser cavity and optics train.....not good.My new 473 is putting out 1/3 above spec and will try to keep it at a stable temp as it creates a lot of heat. You are right about the sink and fan setup. Just not enough. I have a dual 120 watt TEC set that is going to be underneath the laser mounting plate and should have plenty of cooling power.I have had good luck with Arctic silver thermal compound....I get it cheap
Just my .02

[LaserLover]

I have set the PID controller to 25 deg C. I was warned about frost building inside the laser cavity and optics train.....not good.My new 473 is putting out 1/3 above spec and will try to keep it at a stable temp as it creates a lot of heat. You are right about the sink and fan setup. Just not enough. I have a dual 120 watt TEC set that is going to be underneath the laser mounting plate and should have plenty of cooling power.I have had good luck with Arctic silver thermal compound....I get it cheap
Just my .02

Did you set the PID controller on your external peltier cooler for 25 C or did you change the PID level for the internal TEC cooler of the laser head ?
120 watts is a lot of cooling power !
I think you can safely drop the cooling to 20 C without any worries about internal condensation in tha laser head but again that depends on the ambient temperature in which it will operate and the dew point.

Rick

[MechEng3]

This was the setting for the external units.I may drop it to 23 deg C but most of the time the ambient temps are around are 26 to 28 deg C. This was a good benchpoint to start with and seemed to work well. There is a lot more humidity to deal with here in my area....in summer time the most. Common days would be upper 80's with 60 to 100 % humidity. The A/C systems have to really work during those times. Unless I am doing an outdoor show. Then it may become an issue. I always let the projector normalize before powering up. The peltiers I use are 12 volt units and seem to be more tame than the 5 volt units as far as hitting a target temp and holding it. Still keeping in mind that they work in accordance with ability to expell heat and invironment temps. May just be my controller. It is the Auber SYL1512. They have a good track record and are seen a lot on many applications. Very user friendly.

[allthatwhichis]

Yea, you have to remember the dew point down here is MUCH higher than up there. I saw 16C and thought you'd have to have condensation somewhere, then I saw your location. Anything below 22C around the SE US and it gets soggy. :roll: I learned that try to extreme cool computers. It almost hamstrings TECs. I want sub zero but no ice... :?

[LaserLover]

This was the setting for the external units.I may drop it to 23 deg C but most of the time the ambient temps are around are 26 to 28 deg C. This was a good benchpoint to start with and seemed to work well. There is a lot more humidity to deal with here in my area....in summer time the most. Common days would be upper 80's with 60 to 100 % humidity. The A/C systems have to really work during those times. Unless I am doing an outdoor show. Then it may become an issue. I always let the projector normalize before powering up. The peltiers I use are 12 volt units and seem to be more tame than the 5 volt units as far as hitting a target temp and holding it. Still keeping in mind that they work in accordance with ability to expell heat and invironment temps. May just be my controller. It is the Auber SYL1512. They have a good track record and are seen a lot on many applications. Very user friendly.

Interesting, you being in Florida, it's also the state with the most lightning strikes in the US.
If I recall correctly stats over a period of 10 year from 1990 to 2000 there were 151 people killed by lightning in Florida.
Too many open spaces with not enough tall trees to take the hit, all those golfers not making it back to the 19th hole.
What were they thinking when they decided to launch rockets from Cape Canaveral and how many storms have grounded launches with lightning hitting the shuttle, etc...

Rick

[buffo]

Rick;

You're referring to this map by the National Lightning Safety Institue, right?

Yeah, Florida gets a lot of lightning. Most people think of Kansas, Oklahoma, or Texas, but Florida is the king.

As to why they launch rockets from there - well, I've got a feeling it has a lot more to do with orbital mechanics than lightning safety. (It's pretty far south, yet there isn't any land downrange for nearly 4000 miles - unlike Texas, where debris from a failed launch could land in Florida...)

Adam