Applications

  • Wavelength (Color) Separation
    Before: Very low contrast exists between a white date and lot code and a yellow background.
    After: A BP470 Blue Bandpass Filter placed over the camera lens results in excellent contrast. The BP470 blocks the yellow portion of the spectrum, greatly darkening the background, thus resulting in the white lettering standing out.
  • Wavelength (Color) Separation
    Original Color Image
    Before Filter
    After Filter
  • Block Unwanted Light
    Before: Ambient light interferes with detection of a 2D matrix code on a reflective metallic part illuminated with a red 625nm LED light.
    After: Using a BP635 Light Red Bandpass filter over the lens together with red LED illumination, the filter removes reflected ambient light and lightens the appearance of the 2D code to improve overall image quality.
  • Block Unwanted Light
    Before: The presence or absence of green thread sealant is difficult to detect on bolt threads. The parts are illuminated with 625nm red LED lighting.
    After: In a monochrome application, a BP635 Light Red Bandpass Filter placed over the camera lens used in conjunction with red LED illumination results in areas with green sealant appearing almost black in color.
  • Block Unwanted Light
    Before: Without a filter and illuminated under strong ambient white light, there is not enough contrast to be able to reliably read the inkjet date/batch code printed in blue on the bottom of a red plastic coffee can.
    After: A BP635 Light Red Bandpass Filter mounted to the lens, together with 625nm red LED lighting, greatly lightens the background while darkening the printed code. The printed numbers and lettering become much easier to read.
  • Block Unwanted Light & Reduce Glare
    Before: Lack of contrast between the cookie dough and chocolate chips, in addition to cellophane packaging glare caused by ambient light, challenges the accurate counting of chocolate chips in cookies.
    After: A BP660 Dark Red Bandpass Filter mounted on the lens lightens reflections and blocks interfering ambient light, resulting in improved contrast.
  • Block Unwanted Light
    Before: Detecting the characteristics of the projected 670nm laser lines are difficult under white light illumination.
    After: A BP660 Dark Red Bandpass darkens the background of the speedometer and highlights the generated lines, making laser line character analysis possible.
  • Block Unwanted Light
    Before: Wide angle background noise from 532nm laser excitation introduces a bright halo in this image taken through a microarray reader.
    After: An LP550 Orange Longpass Filter blocks the 532nm laser and passes the emission wavelengths – of which there are multiple in this case. Because the LP550 is an absorptive filter glass, it is insensitive to wide angle incident light impinging on the filter. Dichroic (reflective) filters did not achieve acceptable results.
  • Increase Resolution by Reducing Chromatic Aberrations
    Before Filter
    After Filter
  • Increase Contrast & Reduce Glare
    Before: The surfaces of a stent reflect light unevenly, making it difficult to selectively examine desired features.
    After: The use of a PR032 Linear Polarizer and a BP635 Light Red Bandpass Filter, mounted together over the camera lens, eliminates glare and darkens the background to highlight the features of interest.
  • Glare Reduction
    Original Color Image: PCB with flux on copper leads
    Monochromatic Image without Filtering: Copper leads on PCB reflect light, making clear liquid flux detection nearly impossible.
    After Filter: Clear flux detection is made possible with polarizer film used over the DCM High Powered Ring Light and a polarizer filter over the GOYO 35mm Lens.
  • Before: Reflections off of a sealed cap illuminated by ambient light and a white LED light source result in specular glare that renders the cap unreadable.
    After: A PR032 Polarizing Filter installed on the lens and PS030 Polarizing Film over the light source greatly reduces specular reflections.
  • Before: Glare from the clear outer packaging prevents proper imaging of an electrical socket.
    After: A PR032 Polarizing Filter over the lens and PS030 Polarizing Film over the light source reduce glare significantly.
  • Before: Multiple beer bottles imaged at the same time present dark, specular, cylindrical surfaces that are challenging to image because of their tendency to produce glare no matter how the bottles and lighting may be oriented.
    After: Polarizing filters used in tandem over the lens and light source significantly reduce glare from the application lighting. In addition, due to the curvature of the bottle, ambient light also creates glare, so a BP635 Light Red Bandpass filter used together with 625nm red LED lighting effectively eliminates glare completely.
  • Fluorescence Imaging
    Before: A UV LED ringlight is placed in the field of view, creating a ring of bright points of light as well as noise in the background of this image of a UV excited 2D code emitting blue light.
    After: A BP470 Blue Bandpass Filter effectively blocks light emitted by the UV LEDs, passing only blue wavelengths produced by the fluorescence emission
  • Fluorescence Imaging
    Before: Hundreds of tiny plastic particles in the bottle cap reflect light at certain angles, creating noise in the background. This interferes with the ability to inspect the characters printed on the cap.
    After: A Linear Polarizer Filter mounted on the lens and properly aligned extinguishes the direct reflection of light from the particles, eliminating background noise entirely.
  • Before: Reflected glare from shiny, curved surfaces affect the performance of the camera’s auto-gain feature and interferes with reliable pattern detection.
    After: Linear Polarizing Filters on the lens and light source, carefully aligned for maximum glare extinction, completely eliminate specular reflections off of the offending part, thus narrowing the dynamic range.
  • Reduce Glare & Increase Color Saturation
    Before Filter
    After Filter
  • Reduce Glare & Increase Color Saturation
    Before Filter
    After Filter
  • Reduce Glare & Increase Color Saturation
    Before Filter
    After Filter
  • Pass IR & Block VIS Wavelengths to Increase Contrast
    Before: Barcodes on the bottle labels interfere with accurate reading of the shipping label barcode on the outer packaging. Infrared LED illumination alone does not create sufficient contrast.
    After: A BP850 near-IR Bandpass Filter on the camera separates the outer shipping label from the bottle labels. The bottle labels become invisible in the near infrared, resulting in absolute maximum contrast.
  • Pass IR & Block VIS Wavelengths to Increase Contrast
    Before: Without a filter, the edge where two different fabrics meet is difficult to detect.
    After: An 850nm near IR Bandpass Filter mounted on the lens, together with an 850nm LED spot light, provides significantly greater contrast. The fabric on the left reflects infrared light, while the fabric on the right absorbs infrared light, creating contrast.
  • Fluorescence Imaging
    Before: Light from a UV LED light source overpowers blue fluorescence emitted by this part, making the characters virtually undetectable.
    After: A BP470 Blue Bandpass Filter threaded to the lens blocks the overpowering UV light source, passing only the blue emission in the area of interest.
  • Fluorescence Imaging
    Before: The contrast between the UV-excited blue fluorescence and background is not sufficient to reliably image the code marking.
    After: A BP470 Blue Bandpass Filter darkens the background by blocking reflected UV light used to excite the blue fluorescence, creating sufficient contrast.
  • Fluorescence Imaging
    Before: An unfiltered Cognex Checker camera has difficulty distinguishing the presence or absence of a dark grease that is applied to a black seal in two locations. In this case, a Spectrum Illumination SP1.25-395nm UV light is used to cause the grease to fluoresce a light blue color; however contrast between the grease and the area around the grease is very low.
    After: Adding a BP470 Blue Bandpass Filter to the lens blocks interfering UV and ambient light, providing outstanding contrast between the phosphorescent grease and surrounding material.
  • Fluorescence Imaging
    Before: Without a filter over the lens, the 395nm LED light overpowers the fluorescence emission that would allow the 2D matrix to be read by the camera.
    After: A BP470 Blue Bandpass Filter mounted on the camera lens effectively blocks UV wavelengths, passing only the blue fluorescence emission from the 2D matrix while blocking all other unwanted light.
  • Fluorescence Imaging
    Before: UV excited 2D matrix with a cyan fluorescence that is nearly overwhelmed by a UV light source and ambient light.
    After: A BP505 Cyan Bandpass Filter used on the lens blocks the UV light source and other ambient light, passing the cyan fluorescence and thus creating necessary contrast.
  • Fluorescence Imaging
    Before: A postal bar code printed on the back of an envelope for high speed sorting is excited under UV light. Without a filter on the camera, the orange characters go undetected. In this case, the camera sensor is overcome by visible and UV output from the light.
    After: A BP590 Orange Bandpass Filter mounted on the lens creates greater contrast by passing the orange fluorescence while blocking UV, near-IR and other visible wavelengths.
  • Reduce Light Intensity
    Before: The camera lens iris is set to f/16, the smallest aperture available. Still, over-saturation caused by the light that is under inspection results.
    After: With the iris set to f/16 and a ND200 (1% transmission) Neutral Density Filter mounted over the lens, overall transmission is uniformly decreased to manageable levels. Individual lighting elements can be distinguished.
  • Before: The image without filtering clearly displays the effect of very high temperatures, high light intensity, and image saturation.
    After: An IR blocking Shortpass and Neutral Density Filter can be combined to eliminate high-temperature saturation of an image. The threading together of SP645 and ND060 filters onto the lens reduces overall intensity, “blooming”, and unnecessary red and near-infrared light.
  • Ultraviolet Imaging
    Before: Illumination by a UV light source without a filter over the camera lens does not provide enough contrast to differentiate between the plastic substrate and the background.
    After: The UV light source together with a MidOpt BP324 UV Bandpass Filter on the lens enhances contrast to highlight imperfections in the plastic.
  • Block IR Wavelengths for Natural Color Rendition
    Before: Camera without IR and UV block filter, non-visible light interferes with accurate color rendition.
    After: SP700 Near-IR/UV Block-Visible Filter blocks UV and IR to create true-to-eye images
  • Natural Color Balancing
    Before: Under traditional white LED lighting (5000K color temperature), it is difficult to find the adhesive edges of the sticky notes – particularly in the case of the blue and green “flags”.
    After: A LA120 Color Balancing Filter mounted onto the camera lens warms the color temperature, removing the bluish tint caused by “cool” white LED illumination.
  • NDVI Agricultural Inspection
    Visible Light Image
    Raw NDVI Image
    NDVI False Color Processed
  • NDVI Agricultural Inspection
    Image acquired using DB660/850 filter
    DB660/850 acquired image processed for NDVI