How to tell if a green laser pointer is DPSS or green diode?

[laserpointersarecool]

I honestly don't think my green laser has a green diode but i would love to see if there is a method to see if it's true. So, ist there any method (preferably without disassembling into the individual parts)

 

[CurtisOliver]

There are a few ways of telling green dpss and diodes apart. One easy but not foolproof method is wavelength or the colour. DPSS greens are typically 532nm which has a slightly yellower green to it. Diode greens are usually between 510-525nm. Some 530's do exist which is why it isn't foolproof. The colour of these are closer to true green or traffic light green depending on the country.

DPSS have better beam profiles than most diodes. The diode will usually have a slightly rectangular dot whereas the DPSS will have a almost perfect round dot.

Do you notice power fluctuations depending on the operating temperature? DPSS relies on laser crystals and non linear crystals to generate green photons. The KTP crystal in particular likes to be warm. So power drops or failed output tends to occur when the laser is cold. And will gradually output better once warmed up a bit. Diodes don't suffer from this as dramatically. Diodes instead wavelength shift by temperature tuning where DPSS lasers don't.

These are the ones I would start with personally to tell them apart.

 

[julianthedragon]

Where is this laser from? 532 DPSS if they are made well have an in-built IR filter to block invisible IR wavelengths leftover from the DPSS process. So if you want to check the safety of your laser and whether it’s DPSS at the same time, you could get laser glasses that block green light and a cheap IR indicator card (shouldn’t be more than $15). Then hold glasses in front of laser and put indicator on the other side, such that the glasses are between the laser and indicator. If you see a dot on the card, you have an unsafe (IR leaking) DPSS laser. If there is no dot, you still won’t know if you have a safe DPSS or a diode laser, but since you believe it’s more likely you have a DPSS and you might run into similar questions in your future it might be worth doing.

Also, if your laser was inexpensive and high powered in the realm of 1W+, it’s likely diode

 

[laserpointersarecool]

renkforce Laserpointer RF-LP-500

 

[julianthedragon]

Not too hard to find

 

[HunterJackson]

Green Dpss lasers are usually 532nm whereas direct diode ones are around 520~525nm. Direct diode is much stronger than dpss so if you have a high powered 1w+green laser it's most likely direct diode. Green dpss lasers are usually below 500mw. If it's a cheap laser like the chinese built laser 303/301 it's most likely Dpss.

Hope this helps.