Need help with my new CNI laser

[cometchaser]

Hi all, I am new to this forum and also new to the laser world.
I've recently bought a portable laser from CNI directly.
It is a PGL-III-C 500mW 532nm laser. It looks good in build quality. The beam is very bright and beautiful at night and even dusk. But each time I can notice the drop of the brightness of the beam shortly (about 1 minute) after the laser being turned on.

Another problem is about the shape of the laser dot. With my goggles, I can see the dot is not round but changing in shapes. Normally it looks like an oval and then becomes a peanut or double spot. The shift in shapes happens every time from 1 minute after the laser being turned on. I did some research on the net and learned this is called mode hopping.

However, in there data sheet, it says the transverse mode is TEM00. The sales representative also told me not to turn on the laser over 2 minutes (I consider it as the so-called duty cycle). I also asked what is TEM00, they told me the shape of the spot is round.

So my question is: should I return it to the manufacturer for a better one?
Or I have to understand there is no better one because this is not defective.

I would like to know if there is anyone who has the same laser but with a good round dot, not hopping in modes like mine.

I shoot a video which shows clearly the two problems I mentioned.
Thanks for any help!

 

[Speedy78]

Looks like you are just running into thermal issues. DPSS are very sensitive to temperature changes. Some like it warmer thsn others. Yours may like a more cool environment. Does the laser feel warm to touch after a minute?

 

[jeffreythe00]

Send that laser back. It was in TEM01-TEM03 during the entire video! That's unacceptable!

Not to mention that after 2 minutes your laser drops in power so much that you nearly lose all output!

Edit: "Some" modehopping should be expected in these higher powered units. However yours is just in some mode other than TEM00 all the time.

 

[Shakenawake]

I was just about to say basically the same thing. it's some bad mode hopping, and the power reduction is unacceptable. I was going to use that word even before jeffreythe00 did.

usually CNI is pretty good quality, but truth be told, I'd much rather have a 532 by jetlasers or optotronics. I'd include laserglow, but they stopped shipping to the U.S. high power handhelds. If the U.S. is where you live

around here we like it when you make an introduction thread before asking for help. if you don't plan on participating in the forum and only need help this once, I can see why it'd seem pointless. I did the same thing when I was new, asked for help before introducing myself, thinking I wouldn't stick around. now here I am, >500 posts later, addicted

 

[cometchaser]

Thank you Speedy 78!
Yes, the laser is getting warm after about 90 seconds, but not hot. The room temperature is around 20 degrees Celsius.

 

[cometchaser]

Looks like you are just running into thermal issues. DPSS are very sensitive to temperature changes. Some like it warmer thsn others. Yours may like a more cool environment. Does the laser feel warm to touch after a minute?

Thank you Speedy 78!
Yes, the laser is getting warm after about 90 seconds, but not hot. The room temperature is around 20 degrees Celsius.

 

[cometchaser]

Send that laser back. It was in TEM01-TEM03 during the entire video! That's unacceptable!

Not to mention that after 2 minutes your laser drops in power so much that you nearly lose all output!

Edit: "Some" modehopping should be expected in these higher powered units. However yours is just in some mode other than TEM00 all the time.

Thank you jeffreythe00 for your suggestion!
This is the exact information I want to know! I will contact CNI next monday about this issue.

 

[cometchaser]

I was just about to say basically the same thing. it's some bad mode hopping, and the power reduction is unacceptable. I was going to use that word even before jeffreythe00 did.

usually CNI is pretty good quality, but truth be told, I'd much rather have a 532 by jetlasers or optotronics. I'd include laserglow, but they stopped shipping to the U.S. high power handhelds. If the U.S. is where you live
around here we like it when you make an introduction thread before asking for help. if you don't plan on participating in the forum and only need help this once, I can see why it'd seem pointless. I did the same thing when I was new, asked for help before introducing myself, thinking I wouldn't stick around. now here I am, >500 posts later, addicted

Thank you Shakenawake!
I learned in this forum that CNI laser is of high quality. That's why I bought it. The CNIs are the most expensive ones in my area so I thought their quality is the best. So I will probably send it back for a replacement since its problems seem unacceptable.

By the way, I am sorry for not introducing myself before asking for help.
I'm not in the U.S. I live in Xinjiang, China, very far from Beijing and very very far from America as well Well, actually CNI ships lasers to America even faster than to my place. It took 7 days for shipping....

 

[Shakenawake]

lots of people do it, including me, it's a pretty forgive-able offense. you can put your location in your profile so other members know without asking, it helps us help you. doesn't have to be specific, even just the country is usually all the info needed

also, rather than posting multiple times in a row, you can use the edit button, located in the bottom right corner of each post you make in any given thread, to change a post.

I see why you'd go with CNI in that case, this should not have happened to you

 

[cometchaser]

lots of people do it, including me, it's a pretty forgive-able offense. you can put your location in your profile so other members know without asking, it helps us help you. doesn't have to be specific, even just the country is usually all the info needed

also, rather than posting multiple times in a row, you can use the edit button, located in the bottom right corner of each post you make in any given thread, to change a post.

I see why you'd go with CNI in that case, this should not have happened to you

Cool, thank you for your suggestions! I'll try to get familiar with the basics of the forum.
Time to sleep, good night:tired: