• A graph showing the transmission levels across different wavelengths for a bandpass filter, with a peak transmission at approximately 1535nm.
  • Black bandpass filter with technical specifications on a white background
1 2

BP1535-6 Bandpass Filter(CWL=1535nm,FWHM=6nm)

BP1535-6 Bandpass Filter(CWL=1535nm,FWHM=6nm)

PartNumber:SO3010046

$125.00 USD
$125.00 USD
Sale Sold out
Shipping calculated at checkout.
Center Wavelength (CWL) // FWHM
Optical Density // Peak Transmission (Tpk)
Filter Sizes

In Stock.

Ships within 5 working days of order.

Holiday notice: Orders placed Feb 10–25 may ship later than usual. Free shipping applies during this period.
  • Wavelength: 1535nm center wavelength (CWL) for SWIR telecommunications and DWDM applications
  • Spectral Features: 6nm FWHM bandwidth with high transmission and controlled edge slopes
  • Optical Density: OD4 blocking for reliable out-of-band rejection
  • Filter Dimension Availability: Multiple mounting diameters available to fit standard optical systems

Request Raw Data

You can request the raw transmission data from us.

Copy the link of the product page and send email to shop@syronoptics.com, you will get reply within 1 working days.

Shipment & Delivery

  • Stocked products ship within 5 business days after order confirmation.
  • Custom-made products typically ship within 4–8 weeks.
  • Delivery times may be affected by holidays, customs clearance, or other unforeseen events.
  • Tracking information becomes available 3–5 days after dispatch when the parcel is handed to the local courier.
  • Some deliveries may require customer pickup. Please ensure your contact information is correct and respond promptly to courier communications.
  • General international parcel shipping cost: USD 35 (for reference).

Return & Refund

1. Eligible Products

Stocked (catalog) products with a unit price under USD 500 are eligible for return within 14 days after delivery.

Custom-made or non-stock items are not eligible for no-reason returns.

2. No-Reason Return (Buyer’s Remorse)

If you wish to return an item for reasons other than product defect or seller error:

  • Please email shop@syronoptics.com to request a return authorization and return address.
  • Buyer is responsible for all return shipping costs.
  • Items must be unused, in original condition, and with original packaging.
  • Refund will be issued after inspection of the returned item.

3. Seller’s Fault (Defective / Wrong / Damaged Item)

If the return is due to seller error (defective product, wrong item shipped, or damage during shipping):

Please provide clear evidence (photos or videos) showing the issue.

We will evaluate the case and either:

  • Provide a replacement, or
    Issue a refund (with or without requiring the item to be returned).
  • Return shipping cost will be covered by the seller in confirmed seller-fault cases.

4. Important Notes

  • Returned items are subject to inspection before refund approval.
  • Shipping fees, customs duties, and taxes are non-refundable unless the return is due to seller fault.
  • Unauthorized returns will not be accepted.

Custom Sizing

Custom sizing is available from 3 × 3 mm (or Ø5 mm) up to 60 × 60 mm. For custom cut sizes, please contact shop@syronoptics.com for a quotation.

Pricing is not significantly lower for small-size orders in low quantities due to operational costs.

Payment Terms

Payments can be made online using Credit Card, Apple Pay, Google Pay, WeChat Pay, and Alipay.

If you prefer to pay by bank transfer, please contact shop@syronoptics.com to request an invoice with our banking details.

If you require deferred payment terms, you may request NET 7 or NET 30 at the time of placing your order.

All requests for deferred payment are subject to approval and will be confirmed by SyronOptics via email.

View full details
  • BP1535-6 Bandpass Filter - Laser Rangefinding (LRF)

    BP1535-6 Bandpass Filter - Laser Rangefinding (LRF)

    Laser Rangefinding (LRF)

    This is the primary application. Military and commercial rangefinders use this filter on the receiver to block sunlight and ensure they only detect the returning laser pulse.

    Recommended Light Sources

    To use this filter effectively, you must use a light source that emits precisely at 1535 nm.

    • Er:Glass Lasers (Erbium-Doped Glass):Type: Solid-state laser.Use Case: This is the standard source for high-energy, long-distance laser rangefinding (1–20 km). It emits a powerful pulse exactly at 1535 nm.
    • 1535 nm Laser Diodes:Type: Semiconductor laser.Use Case: Used for shorter-range applications, communications, or illumination. They are more compact but typically have lower pulse energy than Er:Glass.
    • ASE Sources (Amplified Spontaneous Emission):Use Case: Sometimes used in testing or optical communications, though less common for the "BP1535-6" narrow filter application compared to pulsed lasers.
  • BP1535-6 Bandpass Filter - Free-Space Optical Communications

    BP1535-6 Bandpass Filter - Free-Space Optical Communications

    Free-Space Optical Communications

    Used to filter noise in secure optical communication links that operate in the SWIR band.

    Recommended Light Source

    • For the Free-Space Optical Communications (FSOC) application using a BP1535-6 Bandpass Filter, the recommended light source is a 1535 nm Distributed Feedback (DFB) Laser Diode.

Fequently Asked Questions

What are the Thickness of the Optical Filters?

For standard mounting (mounted,non-thread):

  • 3.5mm (by default)
  • 6mm (by request)

For unmounted Optics:

  • 0.5mm
  • 1.1mm
  • 2mm

(most of the unmounted optics are having thickness of 1.1mm ~ 2mm)

What is the difference between mountings?

Unmounted:

  • a bare glass optical filter

Mounted:

  • Smooth Mount for protection of the optics. No thread is there on the mount.

Metric Mount:

  • Start with M as prefix, usually seens as M25.5x0.5mm. Mostly used as camera filters

Imperial Mount:

  • Start with SM as prefix, usually seen SM1, SM05 etc... Mostly used in Optical system. (You will have a SM external thread to connecting to other objects)

C-Mount:

  • Very frequently used mounting. C-Mount is 1‘’-32TPI. And it is not the same thing as SM1, or M25.5x0.5mm.

  • dia12.5mm(unmounted)

    Clear Aperture:

    >90%

    Mounting Thickness:

    n.a

    Internal/External Thread:

    n.a/n.a

  • dia12.5mm(mounted)

    Clear Aperture:

    dia9mm

    Mounting Thickness:

    3.5mm

    Internal/External Thread:

    n.a/n.a

  • dia25mm(unmounted)

    Clear Aperture:

    >90%

    Mounting Thickness:

    n.a

    Internal/External Thread:

    n.a/n.a

  • dia25mm(mounted)

    Clear Aperture:

    dia21mm

    Mounting Thickness:

    3.5mm

    Internal/External Thread:

    n.a/n.a

Need any help?