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Spectral transmission graph with a peak at around 400 nm on a white background
  • Spectral transmission graph with a peak at around 400 nm on a white background
  • Blue bandpass filter with black rim on a white background
BP420-10 Bandpass Filter(CWL=420nm,FWHM=10nm)

BP420-10 Bandpass Filter(CWL=420nm,FWHM=10nm)

SO3010128

Center Wavelength (CWL) // FWHM
Center Wavelength (CWL) // FWHM
CWL=420nm // FWHM=10nm
Optical Density // Peak Transmission (Tpk)
Optical Density // Peak Transmission (Tpk)
OD6@200-1100nm // T＞92%
SO3010128-d12.5u
In stock
$55.00
$55.00
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Stock Availability

Yes. Listed filters are generally available from stock, but final availability may depend on size and quantity.

  • Most filters are kept as medium-sized coated pieces
  • Final size is usually diced before shipment
  • Preparation time may vary for urgent orders, custom sizes, or larger quantities
Custom Size & Mounting

We can usually cut optical filters to custom outer sizes, depending on available coated material.

Custom size
  • Typical custom size range: 3 × 3mm to 60 × 60mm
  • Custom sizing changes the outer dimension only
  • Thickness normally follows the original filter specification
  • Final feasibility depends on coated material size and cutting requirements
Mounting
  • Standard mounting options are
    dia12.5mm (mounted) - OD = dia12.5mm,Thickness=3.5mm,No Thread
    dia25mm (mounted) - OD = dia25mm,Thickness=3.5mm,No Thread
  • Mounted options can include non-threaded or threaded mounts
  • Custom mounting may be possible depending on quantity and mechanical requirements
Note
  • Please send the required size, quantity, mounting type, and product link before ordering.
Request Raw Data

Yes. You may request the transmission curve or related spectral data for engineering review.

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

We ship optical products to most supported regions, with shipping cost and delivery method confirmed before payment.

Shipping cost
  • Shipping is generally USD 5–40 per parcel
  • Orders above USD 300 are eligible for free shipping
  • Final cost depends on destination, package size, order value, and shipping method
  • Shipping cost is shown during checkout or confirmed before payment
Shipping coverage
  • We generally ship to Europe, North America, Asia, the Middle East, and Oceania
  • Some countries may be unavailable depending on logistics or customs conditions
Delivery time
  • Most stocked products need 1–5 working days for preparation before shipment
  • After shipment, delivery time depends on destination and shipping method
  • Tracking information will be provided when available
Note
  • If your destination is not available during checkout, please contact us before ordering.
Payment & Quotation

You can order online, request a quotation, or use bank transfer depending on your purchasing process.

Can I request a quotation before ordering?
  • Yes, formal quotations are available before payment
  • Recommended for company purchases, larger quantities, custom sizes, or special shipping requirements
  • Please send the product link, quantity, destination country, and billing details if available
What online payment methods are available?
  • Credit card
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  • Google Pay
Do you support bank transfer?
  • Yes, bank transfer is available
  • We support multi-currency payment through local banking where available
  • Local receiving accounts may include US, UK, Germany, Singapore, and Hong Kong bank accounts
  • For payment in Chinese RMB inside Mainland China, please contact our local partner
  • VAT fapiao may be supported for eligible Mainland China transactions
Do you support company purchase orders?
  • Company purchase orders may be supported after confirmation
  • Please contact us before ordering if your organization requires PO processing, quotation, or invoice matching
Are NET payment terms available? (Pay after received)
  • NET 7 or NET 30 terms may be available for eligible organizations
  • Approval depends on company type, order value, payment history, and internal review
  • Please contact us before ordering if you need NET payment terms
Import, Duties & Customs

mport duties, taxes, and customs handling depend on your destination country and shipping method.

Are duties and taxes included?
  • For express courier services such as DHL or FedEx, duties, taxes, and customs handling are usually paid by the buyer
  • The final import cost depends on destination country, declared value, and local customs rules
  • Duties and taxes are not included unless clearly confirmed before payment
Can SyronOptics help with import clearance?
  • Import-handled delivery may be available for selected regions
  • Supported regions may include USA, Canada, United Kingdom,Europe, Mainland China, Hong Kong, Singapore, Australia, and New Zealand
  • With import-handled delivery, we help arrange clearance and local delivery
  • This option may be slower than express courier
Note
  • If you are not sure, please contact us to confirm whether import-handled delivery is supported in your region.

This BP420-10 Bandpass Filter is designed to transmit a narrow band around 420 nm while reducing out-of-band light. It is suitable for machine vision, fluorescence imaging, and optical inspection systems using blue LED or laser illumination. It helps isolate the target signal, reduce background light, and improve contrast.

Key specifications:

  • Wavelength / main spec: 420 nm center wavelength (CWL)
  • Bandwidth / transition spec: 10 nm FWHM
  • Transmission / blocking: T >92%; OD6 blocking from 200-1100 nm
  • Format / custom option: Available in Dia 12.5mm to dia 34mm (mounted/unmounted), M25.5x0.5mm to M55x0.75mm(mounted); Custom sizes and mounting options available on request

Spectral Data & AOI Review

Filter curves can shift when the filter is used at an angle.

SyronOptics can review spectral data and selected AOI examples to help check whether a filter fits the actual optical path.

LIDT Reference (1064nm)

Selected 1064nm laser damage test data is available for reference when reviewing similar laser-related filter designs.

Final suitability depends on the actual laser condition, coating design, beam size, and system setup.

Custom Size Cutting

Coated filter plates can often be cut into smaller formats for custom optical assemblies.

For narrow bandpass filters, usable area and size may depend on coating uniformity across the larger piece.

BP420-10 Bandpass Filter - Cyan Fluorescent Protein - CFP

BP420-10 Bandpass Filter - Cyan Fluorescent Protein - CFP

Cyan Fluorescent Protein - CFP

  • Role: This filter is likely used as an Excitation Filter.
  • Why: CFP (Cyan Fluorescent Protein) has an excitation peak around 433 nm, but 420 nm is frequently used to excite it while avoiding "cross-talk" with other dyes (like YFP) in FRET (Fluorescence Resonance Energy Transfer) experiments.
  • Function: The filter cleans up the light source, ensuring only 420 nm violet light hits the sample. The OD6 blocking prevents any green or red light from the source from leaking through, which would otherwise wash out the faint fluorescence signal.

Recommended Light Sources

1. High-Power Violet LED (Recommended)

  • Why it's best: Modern fluorescence microscopy uses specific LEDs (often centered at 420 nm or 425 nm).
  • Fit: This is the most efficient match because the LED's output naturally overlaps with your 420 nm filter passband. Unlike broad lamps, it wastes very little energy and generates minimal heat.
  • Stability: LEDs provide the stable intensity required for sensitive FRET measurements.

2. Metal Halide or Mercury (Hg) Arc Lamp

  • Why it works: These are traditional broad-spectrum sources.
  • Fit: While Mercury lamps have a massive peak at 405 nm, they also produce a "continuum" of light in the violet region (400–450 nm). Your BP420-10 filter effectively "slices out" the specific 420 nm portion of this continuum to excite the CFP.
  • Note: This is less efficient than an LED but is standard in many older microscope setups.

3. Supercontinuum White Light Laser

  • Why it works: For advanced confocal or high-end imaging.
  • Fit: These lasers provide a high-intensity white light that acts like a lamp but with laser precision. The filter is used to select the exact 420 nm line from the white spectrum.
BP420-10 Bandpass Filter - Machine Vision (Violet Fluorescence)

BP420-10 Bandpass Filter - Machine Vision (Violet Fluorescence)

Machine Vision (Violet Fluorescence)

  • Role: Imaging Filter.
  • Why: Some industrial materials (glues, optical brighteners, security inks) fluoresce when hit with UV or violet light.
  • Function: If you are blasting a sample with a broad light but only want to see the 420 nm reflection/fluorescence, this filter isolates that specific feature while blocking all ambient light (sunlight, overhead room lights).

Recommended Light Sources

365 nm UV LED

  • Why 365 nm? To see fluorescence at 420 nm, you must hit the sample with higher-energy light (shorter wavelength). This is called the Stokes Shift.
  • 365 nm provides excellent separation from your 420 nm detection window.
  • Your filter (OD6 blocking) will completely block the 365 nm reflection, allowing the camera to see only the glowing glue or ink against a black background.

Similar 420nm Bandpass Filters

Product FAQs

What is the difference between unmounted, mounted, and threaded filter options?

For size options, unmounted and mounted filters use different size references.

Unmounted filters
  • Listed size refers to the actual filter size
  • Example: 12.5mm unmounted means the bare filter is 12.5mm in diameter
Mounted filters
  • Listed size usually refers to the outside size of the mount
  • The filter inside is typically smaller than the mount
  • Example: 12.5mm mounted means the mount outside is 12.5mm, while the filter inside is slightly smaller
  • The inside filter is usually about 1–1.5mm smaller than the mounted outer diameter
Mount type
  • Mounted does not automatically mean threaded
  • If only labeled as mounted, it usually means a smooth, non-threaded mount
  • Threaded mounts should specify a thread standard, such as M25.5 × 0.5mm or SM1
Note
  • If your system has strict requirements for outer diameter, clear aperture, thickness, or thread standard, please confirm before ordering.

How thick is the optical filter?

Filter thickness depends on whether the filter is supplied unmounted or mounted.

Unmounted filters
  • Usually 0.5mm–2mm
  • Common thicknesses: 0.5mm, 1.1mm, 1.5mm
  • Other cases may range from about 0.3mm–3mm
  • Thickness may vary by substrate, coating design, or customer requirement
Mounted filters
  • Total outside thickness depends on the mount structure
  • Non-threaded mount: usually around 3.5mm or 6mm
  • Metric threaded mount: usually around 6.5mm–7.5mm
Note
  • If your system has a strict thickness limit, please confirm the required thickness before ordering.

How is the filter fixed inside the mount?

The fixing method depends on whether the mount is threaded or non-threaded.

Non-threaded mounts
  • Filter is usually fixed with adhesive
  • The filter is secured inside the mount after assembly
  • The filter is generally not removable after mounting
Threaded mounts
  • Filter is usually held with a retaining ring
  • Adhesive is usually not required
  • The filter can usually be removed or replaced later
Note
  • If you need the filter to be removable, please request a threaded mount with retaining ring before ordering.

Can this filter be used at a non-normal angle of incidence?

Yes, but the spectrum may shift when the filter is used away from normal incidence.

Narrow bandpass filters
  • Around 10nm FWHM: small angles such as 0–5° usually have limited effect
  • At 10–15°, wavelength shift may become noticeable
  • Tight spectral systems should check AOI carefully before ordering
Wide bandpass filters
  • Around 50–100nm FWHM: usually more tolerant of angle shift
  • Around 15–20° may still be acceptable in some systems
  • Final suitability depends on the required passband and blocking range
Note
  • Non-normal incidence may also introduce polarization-related effects
  • If your system uses larger AOI, polarized light, or tight wavelength tolerance, please confirm before ordering.

Can you test the filter at different angles of incidence?

Yes. We can provide AOI (angle-of-incidence) testing at selected angles.

AOI testing options
  • Common test angles: 5°, 10°, 15°, 20°, 30°
  • Used to review wavelength shift under non-normal incidence
  • Suitable for laser, imaging, or angle-sensitive optical systems
Cost
  • USD 35 per angle
  • Minimum: 2 angles per request
Note
  • AOI testing can be requested before placing an order
  • This allows you to review measured performance before confirming system compatibility

What if I am not sure which filter fits my system?

If you are not sure, testing a sample in your own system is often the best way to confirm fit.

Sample testing
  • Available for eligible company, laboratory, university, or research-group customers
  • Usually applies to products or orders below USD 150
  • You may test first and pay only if the filter works for your system
Return after testing
  • If the filter is not suitable, you may return it after testing
  • Return approval depends on product condition and review
  • Custom, modified, damaged, or contaminated products may not be eligible
Note
  • Please contact us before ordering if you want to check whether sample testing is available.

Need Help Confirming This Filter?

Whether you are replacing an existing part or building a new system, send us:

- Original part number or target specification
- Required size and quantity
- Application or system goal

We will help check product fit or suggest a stock/custom alternative.