• Graph showing the transmission rate on the y-axis against wavelength in nanometers on the x-axis, for a bandpass filter with a central wavelength of 525nm and a bandwidth of 40nm.
  • Green bandpass filter with black rim on a white background
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BP525-40 Bandpass Filter(CWL=525nm,FWHM=40nm)

BP525-40 Bandpass Filter(CWL=525nm,FWHM=40nm)

PartNumber:SO3010243

$50.00 USD
$50.00 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.
  • Wavelength: 525nm center wavelength (CWL) for green light applications
  • Spectral Features: 40nm FWHM bandwidth balancing selectivity and throughput
  • Optical Density: OD5+ blocking for superior out-of-band rejection
  • Filter Dimension Availability: Multiple mounting options 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
  • BP525-40 Bandpass Filter - Fluorescence Imaging & Microscopy

    BP525-40 Bandpass Filter - Fluorescence Imaging & Microscopy

    Fluorescence Imaging & Microscopy

    This is the most common high-precision application. The filter is used as an emission filter to detect green fluorescence from biological samples stained with fluorophores.

    • Target Fluorophores: FITC, GFP (Green Fluorescent Protein), Eosin, and Alexa Fluor 488, which all emit light in the 515–535nm range.

    Recommended Light Sources

    • Green LEDs (520nm - 530nm):This is the ideal match. High-power green LEDs typically center around 520nm or 525nm. The filter transmits this light with maximum efficiency while blocking ambient light.
    • 532nm Lasers:Common green lasers (like green laser pointers or industrial alignment lasers) operate at 532nm. This falls perfectly within the filter's transmission window.
    • Broadband Sources (White Light):Xenon Arc Lamps or White LEDs: If you use a white light source, this filter will discard roughly 2/3 of the spectrum (red and blue) and output only the pure green component. This is useful for color-sorting applications.
    • Mercury (Hg) Arc Lamps:These lamps have a strong emission line near 546nm, which sits just at the edge of a 525nm/40nm filter (505-545nm). Depending on the steepness of the filter's cutoff, it might attenuate this line slightly, so a 532nm laser or LED is a safer choice.
  • BP525-40 Bandpass Filter - Laser Line Clean-up or Isolation

    BP525-40 Bandpass Filter - Laser Line Clean-up or Isolation

    Laser Line Clean-up or Isolation

    It is frequently used with 532nm lasers (Frequency-doubled Nd:YAG). It can clean up the laser's spectral output by removing "pump light" or other spurious noise, or isolate the laser signal in a system with multiple laser lines.

    Recommended Light Sources

    1. Standard Industrial Green Laser Modules (Best for DIY/Integration)

    These are the most common sources. They are compact "Diode Pumped Solid State" (DPSS) modules used for alignment or building into larger machines. They are bright and affordable, but they are the most likely to have "noise" (IR leakage) that your filter needs to clean up.

    • Look for: "532nm Green Laser Module" or "DPSS Green Laser."
    • Typical Power: 5mW to 100mW.

    2. Lab-Grade DPSS Laser Sources (Best for Precision)

    If you are building a fluorescence microscope or a high-end measurement system, you use a lab-grade source. These are more stable and often come with power supplies, but they still benefit from the filter to ensure the background is pitch black for sensitive sensors.

Fequently Asked Questions

Different Types of Filter 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.

What are the Thickness of the Optical Filters?

For Unmounted Optics:

  • 0.5mm
  • 1.1mm
  • 2.0mm

*Most of our optics are coming with 1.1mm and 2.0mm

With Standard Mounting (Mounted, No Thread):

  • 3.5mm (Default)
  • 6mm (Upon Request)

Thread Mounted:

  • 6mm - 8mm

  • 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(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

  • M25.5x0.5mm(mounted)

    Clear Aperture:

    dia20.5mm

    Mounting Thickness:

    6.5mm

    Internal/External Thread:

    M25.5x0.5mm/M25.5x0.5mm

  • M27x0.5mm(mounted)

    Clear Aperture:

    dia22mm

    Mounting Thickness:

    6.5mm

    Internal/External Thread:

    M27x0.5mm/M27x0.5mm

  • M30.5x0.5mm(mounted)

    Clear Aperture:

    dia25.5mm

    Mounting Thickness:

    6.5mm

    Internal/External Thread:

    M30.5x0.5mm/M30.5x0.5mm

  • M34x0.5mm(mounted)

    Clear Aperture:

    dia29mm

    Mounting Thickness:

    6.5mm

    Internal/External Thread:

    M34x0.5mm/M34x0.5mm

  • M35.5x0.5mm(mounted)

    Clear Aperture:

    dia30.5mm

    Mounting Thickness:

    6.5mm

    Internal/External Thread:

    M35.5x0.5mm/M35.5x0.5mm

  • M37x0.5mm(mounted)

    Clear Aperture:

    dia32mm

    Mounting Thickness:

    6.5mm

    Internal/External Thread:

    M37x0.5mm/M37x0.5mm

  • M52x0.75mm(mounted)

    Clear Aperture:

    dia47mm

    Mounting Thickness:

    6.5mm

    Internal/External Thread:

    M52x0.75mm/M52x0.75mm

  • M55x0.75mm(mounted)

    Clear Aperture:

    dia50mm

    Mounting Thickness:

    6.5mm

    Internal/External Thread:

    M55x0.75mm/M55x0.75mm

  • dia27mm(unmounted)

    Clear Aperture:

    >90%

    Mounting Thickness:

    n.a

    Internal/External Thread:

    n.a/n.a

  • dia34mm(unmounted)

    Clear Aperture:

    >90%

    Mounting Thickness:

    n.a

    Internal/External Thread:

    n.a/n.a

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