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510nm pointer for $19 legit?

lazylazer

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A year or two ago the cheapest green laser diode pointer I could find was about $80.

Now I see a 510nm green laser diode pointer for $19.

Any idea if this is a legit deal?
 



RedCowboy

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My laserlands pen is a direct 520nm, I do have laserlands larger silver host that takes 2 x 18350's and it looks like a 515nm, I also pot modded it.
 
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CurtisOliver

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I have the same larger host from Laserland. They are legit. Good that you are questioning legitimacy. :)
 

paul1598419

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I got one too. It measures 510nm even though it is claimed to be a 520nm direct diode.
 

lazylazer

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I ordered the $19 laser from laserland. It arrived after 3 weeks and is DOA.
Using a multimeter I see it draws 1A but no light comes out. When I contacted laserland, they told me to put the batteries in the opposite direction. I did, but of course that didn't work either. I already have three other laser pointers using the same host, so I know the correct battery orientation (negative to spring, positive to case). I'm still waiting for their next advice.

On the positive side, it is well packed. The pointer is in a hard case surrounded by foams pads placed inside a shipping box. Just wish they tested it before shipping.

What is the next least expensive green laser diode pointer that is more reliable?
 

Merpie101

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I ordered the $19 laser from laserland. It arrived after 3 weeks and is DOA.
Using a multimeter I see it draws 1A but no light comes out. When I contacted laserland, they told me to put the batteries in the opposite direction. I did, but of course that didn't work either. I already have three other laser pointers using the same host, so I know the correct battery orientation (negative to spring, positive to case). I'm still waiting for their next advice.

On the positive side, it is well packed. The pointer is in a hard case surrounded by foams pads placed inside a shipping box. Just wish they tested it before shipping.

What is the next least expensive green laser diode pointer that is more reliable?
last time i bought from laserlands i got a DOA laser too... so i made a post about it and then they did a giveaway for them for free and i never got a replacement :(
 
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deadshadow

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I ordered the $19 laser from laserland. It arrived after 3 weeks and is DOA.
Using a multimeter I see it draws 1A but no light comes out. When I contacted laserland, they told me to put the batteries in the opposite direction. I did, but of course that didn't work either. I already have three other laser pointers using the same host, so I know the correct battery orientation (negative to spring, positive to case). I'm still waiting for their next advice.

On the positive side, it is well packed. The pointer is in a hard case surrounded by foams pads placed inside a shipping box. Just wish they tested it before shipping.

What is the next least expensive green laser diode pointer that is more reliable?

Same host doesn't mean same polarity,depends on each diode needs(if the diode is case positive,negative or neutral).you could fried your laser with wrong polarity very well,make sure to ask your supplier to be sure next time
 

paul1598419

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I have been ordering from LaserLands for over 5 years with little, if any, problems. Deadshadow is correct, these pen laser all have different battery polarities and unless you know which it is for a particular laser, you will kill it by putting the batteries in backwards. That is not LaserLand's fault. If you don't know for certain, ask before you put the batteries in.
 
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Benm

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Well, if it runs from standard AAA cells i'd say this is a bit of manufacturing fault or at least oversight, as it is -very- easy to design battery compartments in such a way that cells inserted the wrong way around cannot physically make contact with the electronics.

This approach is very standard in consumer electronics: if you try to put AA or AAA cells in the wrong way around they usually either don't fit at all, or make no electrical connection.

It would be different for a product running from say 18650 lithium cells which are also available without the 'nipple' on the positive side.
 

Razako

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It would be great if manufacturers would adopt a standardized battery scheme which is always followed. Basically the negative side of the battery should go towards the spring. Seems like most things follow this scheme, but every now and then you get some weird product which doesn't.
 

Benm

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It would be great if manufacturers would adopt a standardized battery scheme which is always followed. Basically the negative side of the battery should go towards the spring. Seems like most things follow this scheme, but every now and then you get some weird product which doesn't.
There are some very good reasons why this is not done on -all- lasers.

One thing most have in common is that the housing also serves as one of the electrical connections (normally the spring/endcap one). In case of case-isolated diodes you can choose to follow the convention you mentioned without any problems.

However, there are some laser diodes that have their case connected to the -anode-, most notably 808 nm pump diodes for DPSS lasers. As the diode voltage is also pretty close but lower than the cell voltage (when using lithium at least, or 2 AA/AAA in series), the most practical solution is to have the case connected to the battery positive and use a low drop linear regulator on the negative side.

Sticking to the 'case must be connected to battery negative' would require a voltage inverting switchmode driver that would add nothing in effieciency but a lot in cost and complexity. The only other alternative would be to electrically isolate the laser diode from the pointer body, but that's something you really want to avoid because isolating something electrically usually also means a far worse thermal connection.

So no, it's not just stubborn people and standards, there is in some cases a very good technical reason for it... but you could still design the things such that they do not make physical contact if you have batteries with a nipple on them, or perhaps use a mosfet reverse voltage protection otherwise.
 

Encap

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True lol
:crackup:
Not to mention, who would create and enforce such a "Standard", especially on products like laser pointers all made in China and both illegal to import and sell in USA :crackup:
Fat chance of that even if it made sense to do which it doesn't for real reasons mentioned above by Benm

USA FDA laws, rules, and regulations are more than enough.

A Battery orientation sticker might would solve the problem, if the manufacturer actually cared to solve it.
 
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Razako

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There are some very good reasons why this is not done on -all- lasers.

One thing most have in common is that the housing also serves as one of the electrical connections (normally the spring/endcap one). In case of case-isolated diodes you can choose to follow the convention you mentioned without any problems.

However, there are some laser diodes that have their case connected to the -anode-, most notably 808 nm pump diodes for DPSS lasers. As the diode voltage is also pretty close but lower than the cell voltage (when using lithium at least, or 2 AA/AAA in series), the most practical solution is to have the case connected to the battery positive and use a low drop linear regulator on the negative side.

Sticking to the 'case must be connected to battery negative' would require a voltage inverting switchmode driver that would add nothing in effieciency but a lot in cost and complexity. The only other alternative would be to electrically isolate the laser diode from the pointer body, but that's something you really want to avoid because isolating something electrically usually also means a far worse thermal connection.

So no, it's not just stubborn people and standards, there is in some cases a very good technical reason for it... but you could still design the things such that they do not make physical contact if you have batteries with a nipple on them, or perhaps use a mosfet reverse voltage protection otherwise.
Oh, I wasn't suggesting that the batteries should always have the - to the tailcap. It was more that the spring should always go to the negative. Jetlasers are a great example of this, they're case positive but they have the nipple on the tailcap and the spring inside the laser. I do see how you might have an issue though, when dealing with a host that wasn't originally designed for laser use.

Not to mention, who would create and enforce such a "Standard", especially on products like laser pointers all made in China and both illegal to import and sell in USA :crackup:
Fat chance of that even if it made sense to do which it doesn't for real reasons mentioned above by Benm

USA FDA laws, rules, and regulations are more than enough.

A Battery orientation sticker might would solve the problem, if the manufacturer actually cared to solve it.
The bolded part is the real issue.
 
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