IR-Block/Visible Optical Filters feature 25.4™ C-Mount for installation.

Press Release Summary:

Available in SP635, SP644 and AB555, IR-Block/Visible Optical Filters come with C-Mount for easy installation. SP635 filters are A/R coated on both sides and offer ≥90% peak transmission. Used in cameras with CMOS sensor responsivity, SP644 is used in 395-638 nm range. Having laser protection at 1064 nm, AB555 comes with 3.5 mm thickness and has optical density of UV (190-375nm), near-IR (760-1070nm) and at 10,600nm.

Original Press Release:

New IR-Block/Visible Transmitting Optical Filters from MidOpt

MidOpt announces the availability of three new imaging filters primarily intended for blocking unwanted near-infrared light. Filters include: SP635 Absorptive Visible Shortpass/Near-IR Block Filter, SP644 Near-IR/Mid-Red Dichroic Block Shortpass Filter, and AB555 Acrylic Absorptive Near-IR/UV-Block Visible Bandpass Filter. Mounting solutions are available to help customize any imaging application. MidOpts unique filter mounting options include: Standard Threaded Mounts, Slip Mounts that easily adapt to lenses without filter threads, the exclusive 25.4™ C-Mount for easy installation into cameras, and custom fabrication of unmounted shapes and sizes.

MidOpts SP635 Absorptive Visible Shortpass/Near-IR Block Filter is commonly used inside cameras to block infrared light. When working with any camera that has been modified and its internal IR cut filter has been removed, a SP635 filter mounted on the front of the lens, when desired, can return function once again like the unmodified camera. This is an absorptive infrared rejection filter that is also recommended for protecting a cameras sensor from stray light emitted by lasers or other high power near-IR light sources. SP635 filters are A/R coated on both sides to maximize visible band transmission while offering superior out-of-band blocking. Peak transmission is ≥90%.

SP644 Near-IR/Mid-Red Dichroic Block Shortpass Filter is one of several dichroic filters offered mainly for use as an internal infrared blocking filter in color cameras. This design offers an attractive price/performance option compared to other designs. Uniform blocking of near-infrared wavelengths out to 1100nm, uniformly high transmission across the visible range, and a 50% point in the middle of the red portion of the spectrum make this an ideal choice for cameras with typical CMOS sensor responsivity. SP644 is useful to achieve natural color rendition with superior response in the blue channel. Its useful range is 395-638nm with a peak transmission ≥90%.

The AB555 Acrylic Absorptive Bandpass filter passes light in the visible range and blocks all near-infrared, ultraviolet and violet wavelengths. This filter offers excellent laser protection at 1064nm (O.D. 6). Additionally, optical density exceeds 5.0 in the UV (190-375nm), near-IR (760-1070nm) and at 10,600nm. Standard thickness is 3.5mm. The material is a light greenish color in transmission. Sheet stock can be quickly laser cut to a wide variety of custom sizes and shapes, particularly when used as a cover for an enclosure or a laser protective window.

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About Midwest Optical Systems

Midwest Optical Systems (MidOpt) is a global leader providing stock and custom machine vision filters, lenses, lighting and other precision optical solutions. Represented in over 30 countries and offering over 3,000 standard off-the-shelf products, over 100,000 filters and 50,000 lenses are shipped every year. MidOpt filters are recognized as the industry standard for automated imaging applications to ensure reliable control, repeatable results and superior image quality. All filters are produced to demanding standards regarding durability and spectral, optical and cosmetic characteristics. Unlike traditional filters, MidOpt filters closely emulate the output of all common LED/lighting types and colors. Designs are available to provide optimal performance regardless the application wavelength, ambient lighting, or lens focal length.


Vicki Vassallo

Midwest Optical Systems, Inc. (MidOpt)


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