by Joe Farina » Sun Dec 05, 2010 4:46 pm
Hello Baja,
Straight DCG is most sensitive to blue or violet light, and it's easiest to make DCG with wavelengths around 442 to 488nm. However, that's also the most expensive light, because it needs to have enough coherence length. Blue, highly coherent light is quite expensive. Although I haven't used 532nm for DCG, it can be done quite easily, though as you mention, the sensivity is less, so you have to use a higher percentage of dichromate. To get a feel for things, I would go to the Holography Forum archive at the bottom of the main page of this forum, and put some search terms in the search field like DCG, 532nm, 315M, dichromate, etc. There will be a lot of things to look at, to provide guidance. The 315 is a very good laser. I would suggest the 100mW variety if you're working with DCG, the extra power will come in handy. There might be some good deals out there for blue lasers, just be certain they have enough coherence, and expect to pay more than $1,500, which is about what the 315M goes for.
Hello Baja,
Straight DCG is most sensitive to blue or violet light, and it's easiest to make DCG with wavelengths around 442 to 488nm. However, that's also the most expensive light, because it needs to have enough coherence length. Blue, highly coherent light is quite expensive. Although I haven't used 532nm for DCG, it can be done quite easily, though as you mention, the sensivity is less, so you have to use a higher percentage of dichromate. To get a feel for things, I would go to the Holography Forum archive at the bottom of the main page of this forum, and put some search terms in the search field like DCG, 532nm, 315M, dichromate, etc. There will be a lot of things to look at, to provide guidance. The 315 is a very good laser. I would suggest the 100mW variety if you're working with DCG, the extra power will come in handy. There might be some good deals out there for blue lasers, just be certain they have enough coherence, and expect to pay more than $1,500, which is about what the 315M goes for.