Specs
Johnson-Cousins Filter Specs
Substrate |
3.0mm +/-0.025mm fused silica |
Filter size |
25.4mm +/-0.1mm diameter |
Clear Aperture |
Central 23.4mm diameter minimum |
TWF |
</= 1/4 lambda per any 25mm square area before coating |
Parallelism |
</=0.5 arcminute before coating |
Coating |
To edge of part |
AOI |
0 degree |
Scratches |
</= 0.06mm width; no limit on length |
Particles/Bubbles |
</= 0.4mm dia. |
Pinholes/Voids |
</= 0.2mm dia. |
Edge Finish |
As fabricated |
Chips |
</=0.5mm |
Edge Treatment |
Edges blackened with Enthone M-0-N black epoxy ink |
Thickness |
It may extend 0.5mm onto top and bottom surfaces |
JOHNSON-COUSINS U+
T = 50%: 391.3 nm +/- 3.1 nm
350 nm – 410 nm: match target curve by design, will not evaluate
360 nm – 375 nm: Tmin >= 90%; 430 nm – 1050 nm: Tave <=0.01%
Coating has been redesigned to minimize back reflections with theoretical values < 0.3% average.
JOHNSON-COUSINS Bu+++
T = 50%: 377.0 nm +/- 5.7nm; T = 50%: 473.0 nm +/- 3.8 nm
365 nm – 525 nm: match target curve by design – will not evaluate
410 nm – 425 nm: Tmin >= 90%
300 nm – 350 nm: Tave <=0.01%; 550 nm – 1100 nm: Tave <=0.01%; 560 nm – 1000 nm: Tabs <=0.1%
Back reflections with theoretical values < 0.4% average by design.
JOHNSON-COUSINS V+
T = 50%: 490.0 nm +/- 7.3nm; T = 50%: 589.2 nm +/- 4.7 nm
478 nm – 640 nm: match target curve by design, will not evaluate
518 nm – 532 nm: Tmin >= 95%
300 nm – 460 nm: Tave <=0.01%; 670 nm – 1050 nm: Tave <=0.01%
Coating has been redesigned to minimize back reflections with theoretical values < 0.3% average.
JOHNSON-COUSINS Rc
T = 50%: 567.3 nm +/- 8.5nm; T = 50%: 717.1 nm +/- 5.7 nm
550 nm – 850 nm: match target curve by design – will not evaluate
594 nm – 615 nm: Tmin >= 95%; 300 nm – 525 nm: Tave <=0.01%
900 nm – 1050 nm: Tave <=0.01%; 860 nm – 900 nm: Tave <= 1.0%
JOHNSON-COUSINS Ic
T = 50%: 721.8 nm +/- 10.8nm; T = 50%: 889.8 nm +/- 7.1 nm
705 nm – 900 nm: match target curve by design – will not evaluate
758 nm – 850 nm: Tmin >= 95%
300 nm – 680 nm: Tave <=0.01%; 930 nm – 1050 nm: Tave <=0.01%
Shipping
We know that once you've placed your order, you are anxious to receive it! We make every effort to get your order shipped out to you as quickly as possible.
As soon as you place your order, you will receive an order confirmation e-mail. This means that we have received your order in our system and pre-authorized your credit card for the purchase. We will process the charges to your credit card and your order will ship within five business days from the date of your order. We will send you tracking information within 24 hours of your order leaving the warehouse to the e-mail address you provided when checking out. If you do not receive tracking information from us within six business days of your order, feel free to follow up with us at info@telescopetek.com.
Standard shipping time in the US is between 3-5 business days, though it can vary slightly depending on the destination. We typically For updates on your shipment you can enter your tracking number here.
We distribute nationwide via UPS and Fedex. Unfortunately, at this time we are not able to provide expedited or international shipping.