• Graph showing the transmission verses wavelength for a bandpass filter with a central wavelength of 785nm and a bandwidth of 1nm.
  • Red bandpass filter with black rim on a white background
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BP785-1 Bandpass Filter(CWL=785nm,FWHM=1nm)

BP785-1 Bandpass Filter(CWL=785nm,FWHM=1nm)

PartNumber:SO3010533

$375.00 USD
$375.00 USD
Sale Sold out
Shipping calculated at checkout.
Center Wavelength (CWL) // FWHM
Optical Density // Peak Transmission (Tpk)
Dimension

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: 785nm center wavelength with 1nm FWHM for near-infrared applications
  • Spectral Features: Ultra-narrow bandpass transmission optimized for critical Raman spectroscopy, laser cleanup, and high-precision research applications
  • Optical Density: OD4 blocking for superior out-of-band rejection and signal clarity
  • Filter Dimension Availability: Multiple sizes available to fit your optical system requirements

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
  • BP785-1 Bandpass Filter - Raman Spectroscopy (Laser Line Cleanup)

    BP785-1 Bandpass Filter - Raman Spectroscopy (Laser Line Cleanup)

    Raman Spectroscopy (Laser Line Cleanup)

    This is the primary application. 785 nm is a standard Raman laser wavelength. Diode lasers often emit low-level "spontaneous emission" (background light) at wavelengths other than 785 nm. This filter cleans up the laser source, ensuring only the pure 785 nm excitation light hits the sample, which is critical for detecting weak Raman signals.

    Recommended Light Sources

    • Frequency-Stabilized 785 nm Laser Diode: This is the optimal choice because standard laser diodes can drift by ~0.3 nm/°C; a stabilized source ensures the emission wavelength remains locked within the narrow 1 nm passband of your BP785-1 filter, preventing total signal loss.
    • Single-Mode 785 nm Laser Diode (with Temperature Control): A viable standard alternative, but it requires a Thermo-Electric Cooler (TEC) controller to precisely tune and maintain the laser temperature so the peak emission aligns perfectly with the filter's window.

  • BP785-1 Bandpass Filter - LIDAR & Remote Sensing

    BP785-1 Bandpass Filter - LIDAR & Remote Sensing

    LIDAR & Remote Sensing

    Used to block solar background noise (sunlight) while allowing the specific 785 nm laser return signal to pass through to the detector, improving the signal-to-noise ratio in daylight.

    Recommended Light Sources

    • High-Power Pulsed 785 nm Laser: Generates the high-intensity pulses needed for long-range detection; utilizing a temperature-stabilized model is critical to keep the laser wavelength locked within the filter's narrow 1 nm passband, ensuring maximum signal throughput against bright solar background.

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(mounted)

    Clear Aperture:

    dia9mm

    Mounting Thickness:

    3.5mm

    Internal/External Thread:

    n.a/n.a

  • dia12.5mm(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

  • dia25mm(unmounted)

    Clear Aperture:

    >90%

    Mounting Thickness:

    n.a

    Internal/External Thread:

    n.a/n.a

  • SM05(0.535″-40TPI)

    Clear Aperture:

    dia9mm

    Mounting Thickness:

    7.62mm

    Internal/External Thread:

    SM05/SM05

  • SM1(1.035″-40TPI)

    Clear Aperture:

    dia21mm

    Mounting Thickness:

    7.62mm

    Internal/External Thread:

    SM1/SM1

  • C-Mount(1″-32TPI)

    Clear Aperture:

    dia21mm

    Mounting Thickness:

    Internal/External Thread:

    C-Mount/C-Mount

Need any help?