 | Can I send you a laser to package?
PD-LD, Inc will package customer supplied lasers as long as they are in a sealed TO-can and are received with the lasers specifications. |
| Can I supply my own fiber for pigtailing?
PD-LD, Inc will accept customer supplied fiber. |
| Can you also provide near 100% reflectivity?
We’ve made filters with > 99.99% reflectivity. But it does depend on the thickness of the grating. |
| Do you have a minimum order quantity?
No, but if your order is below $1000.00 and you do not have an account with us, we request that your either prepay your order or pay by credit card. |
| Do you offer small power (100 mW) laser diodes in the near infrared (800 - 900 nm) that are frequency stabilized using VBG?
Currently we offer single emitters on C-mounts that are 1, 2 or 3 Watts in output power and are wavelength-stabilized. Wavelengths are from around 750 nm to upper 900’s of nm. |
| How big are the wafers you can produce with your technology?
Our standard wafers are 20x20 mm right now. In the future we intend to introduce larger sizes. |
| How can I pay for my order?
PD-LD, Inc, accepts all major credit cards. In addition we accept prepayment for orders. If you would like to apply for terms with PD-LD, Inc and your order is above $1000.00 please contact us at 609-564-7900. |
| How do I place an order?
To place your order, you may fill in our contact form, fax your request to the attention of Sales at 609-564-7901, email us at info@PD-LD.com or phone us at 609-564-7900. Please include your Billing/Shipping address, PO number, and method of shipment, part number and quantity you would like to order. |
| How do I receive a quote for a product I am interested in?
In order to receive a quote you may either fill in our contact form, fax your request to the attention of Sales at 609-564-7901, email us at info@PD-LD.com or phone us at 609-564-7900. Please include the part number and quantity required. |
| How should I determine the optimum reflectivity of the VBG when I use it for wavelength stabilization?
We don’t have an exact formula for this. We can tell you that with fast axis collimation only and focal length of that lens ranging from 0.1 mm to 0.9 mm it is sufficient to have a VBG with approximately 40% intrinsic reflectivity (i.e. measured with light collimated on both axis). |
| How stable is the grating on the temperature? What is the usable temperature range?
VBGs have been tested to 200C for up to a couple of weeks without measurable degradation in performance. |
| Is there a big price difference for various reflectivities?
Not until about 90% reflectivity. It is more difficult to make samples with higher than 90% reflectivity. |
| Is there a possibility to tune the reflectivity peak by changing the temperature or other parameters? What is the dLambda/dTemp coefficient?
Yes. The easiest thing is to tune by temperature. The temperature tuning coefficient for our VBG elements is 0.01 nm/K. It is also possible to tune the wavelength in much wider range by rotation. |
| Is there any angular dependence of the peak wavelength? If yes, please give details.
The peak wavelength changes with angle as follows: λ = λc*sqrt(1-sinθ^2/n^2), where λc is the cut-off wavelength, θ is the angle of incidence in air and n is the refractive index of glass. |
| What are your payment terms?
Net 30 days for customers with established credit. |
| What is the damage threshold and long-time stability for these VGBs (example: laser diode bar with emitter 1 umx10 mm, power 50 W)?
We have verified with 30µSec pulses at 1064nm that no damage was observed. |
| What is the optimum reflectivity when used for the above purpose (stabilizing the wavelength of laser diodes at 807.5 nm used in pumping solid-state lasers)?
It depends on the front facet coating, the design of the laser chip as well as the collimation lens. |
| What is the typical thickness of the VGB itself in the glass wafer in
order to achieve the near 100% reflectivity?
The Bragg grating penetrates the entire volume of glass. So the entire 1 mm of glass thickness is the Bragg grating. In 1 mm of glass we have achieved approximately 93% reflectivity at around 800 nm. |
| What is the typical thickness of the wafers?
For wavelength stabilization of the high-power laser diodes and arrays the typical thickness of the VBG element is from 0.5 to 1 mm. |
| What is the useful range of wavelengths?
In general, it is anywhere between 350 and 2500 nm, depending on how much loss you are willing to tolerate. As part of the research, we have actually made recordings at wavelengths from 480 nm to the 1500 nm range. Our wavelength locking products, however, are offered in the 630 to 980 nm range. There are some standard wavelengths in that range that are offered with faster delivery times and at lower prices then others: 785 nm, 808 nm, 938 nm and 976 nm. |
| What was the thickness of your samples with 99.99% reflectivity?
It was upwards of 3 mm, depending on the operating wavelength. |
