Square Colored Glass Alternative Longpass Filters

Our colored glass alternative long-pass edge filters are a great alternative to standard colored glass filters. Featuring Stabilife® coating technology, many layers of refractory metal oxide film are deposited under vacuum in a precise sequence, defining the spectral signature of the filters. Unlike Colored-Glass filters which rely upon absorption to create the filter's spectral response, CGA filters utilize optical interference phenomena to create wide bands of very-high reflectance to create the blocking region of the filters, and wide bands of very-low reflectance to create the transmission bands of the filters.

Steep transitions from blocking to transmission
High transmission of >90% average (typical)
Excellent blocking of >5 OD
Patented Stabilife® coatings
Wavelength stability in any environment

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Showing 31 of 31 total products

Compatibility:

Description	Compatibility	Cut-on Wavelength	Cut-on Wavelength Tolerance	Price
20CGA-305Longpass Filter, Colored-Glass Alternative, 2x2 in., 305 nm Cut-on	UNIVERSAL	305 nm	±5 nm	$138
20CGA-320Longpass Filter, Colored-Glass Alternative, 2x2 in., 320nm Cut-on	UNIVERSAL	320 nm	±5 nm	$138
20CGA-335Longpass Filter, Colored-Glass Alternative, 2x2 in., 335 nm Cut-on	UNIVERSAL	335 nm	±5 nm	$138
20CGA-345Longpass Filter, Colored-Glass Alternative, 2x2 in., 345 nm Cut-on	UNIVERSAL	345 nm	±5 nm	$138
20CGA-360Longpass Filter, Colored-Glass Alternative, 2x2 in., 360 nm Cut-on	UNIVERSAL	360 nm	±5 nm	$138
20CGA-375Longpass Filter, Colored-Glass Alternative, 2x2 in., 375 nm Cut-on	UNIVERSAL	375 nm	±5 nm	$138
20CGA-385Longpass Filter, Colored-Glass Alternative, 2x2 in., 385 nm Cut-on	UNIVERSAL	385 nm	±5 nm	$138
20CGA-395Longpass Filter, Colored-Glass Alternative, 2x2 in., 395 nm Cut-on	UNIVERSAL	395 nm	±5 nm	$138
20CGA-400Longpass Filter, Colored-Glass Alternative, 2x2 in., 400 nm Cut-on	UNIVERSAL	400 nm	±5 nm	$138
20CGA-420Longpass Filter, Colored-Glass Alternative, 2x2 in., 420 nm Cut-on	UNIVERSAL	420 nm	±5 nm	$138
20CGA-435Longpass Filter, Colored-Glass Alternative, 2x2 in., 435 nm Cut-on	UNIVERSAL	435 nm	±5 nm	$138
20CGA-455Longpass Filter, Colored-Glass Alternative, 2x2 in., 455 nm Cut-on	UNIVERSAL	455 nm	±5 nm	$138
20CGA-475Longpass Filter, Colored-Glass Alternative, 2x2 in., 475 nm Cut-on	UNIVERSAL	475 nm	±5 nm	$138
20CGA-495Longpass Filter, Colored-Glass Alternative, 2x2 in., 495 nm Cut-on	UNIVERSAL	495 nm	±5 nm	$138
20CGA-515Longpass Filter, Colored-Glass Alternative, 2x2 in., 515 nm Cut-on	UNIVERSAL	515 nm	±5 nm	$138
20CGA-530Longpass Filter, Colored-Glass Alternative, 2x2 in., 530 nm Cut-on	UNIVERSAL	530 nm	±5 nm	$138
20CGA-550Longpass Filter, Colored-Glass Alternative, 2x2 in., 550 nm Cut-on	UNIVERSAL	550 nm	±5 nm	$138
20CGA-570Longpass Filter, Colored-Glass Alternative, 2x2 in., 570 nm Cut-on	UNIVERSAL	570 nm	±5 nm	$138
20CGA-590Longpass Filter, Colored-Glass Alternative, 2x2 in., 590 nm Cut-on	UNIVERSAL	590 nm	±5 nm	$138
20CGA-610Longpass Filter, Colored-Glass Alternative, 2x2 in., 610 nm Cut-on	UNIVERSAL	610 nm	±6 nm	$138
20CGA-630Longpass Filter, Colored-Glass Alternative, 2x2 in., 630 nm Cut-on	UNIVERSAL	630 nm	±6 nm	$138
20CGA-645Longpass Filter, Colored-Glass Alternative, 2x2 in., 645 nm Cut-on	UNIVERSAL	645 nm	±6 nm	$138
20CGA-665Longpass Filter, Colored-Glass Alternative, 2x2 in., 665 nm Cut-on	UNIVERSAL	665 nm	±6 nm	$138
20CGA-695Longpass Filter, Colored-Glass Alternative, 2x2 in., 695 nm Cut-on	UNIVERSAL	695 nm	±6 nm	$138
20CGA-715Longpass Filter, Colored-Glass Alternative, 2x2 in., 715 nm Cut-on	UNIVERSAL	715 nm	±7 nm	$138
20CGA-760Longpass Filter, Colored-Glass Alternative, 2x2 in., 760 nm Cut-on	UNIVERSAL	760 nm	±7 nm	$138
20CGA-780Longpass Filter, Colored-Glass Alternative, 2x2 in., 780 nm Cut-on	UNIVERSAL	780 nm	±7 nm	$138
20CGA-800Longpass Filter, Colored-Glass Alternative, 2x2 in., 800 nm Cut-on	UNIVERSAL	800 nm	±8 nm	$138
20CGA-830Longpass Filter, Colored-Glass Alternative, 2x2 in., 830 nm Cut-on	UNIVERSAL	830 nm	±8 nm	$138
20CGA-850Longpass Filter, Colored-Glass Alternative, 2x2 in., 850 nm Cut-on	UNIVERSAL	850 nm	±8 nm	$138
20CGA-1000Longpass Filter, Colored-Glass Alternative, 2x2 in., 1000 nm Cut-on	UNIVERSAL	1000 nm	±9 nm	$138

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Notes:

CGA filters are also available in Round shape.

Specifications

Type
Colored-Glass Alternative Longpass Filter
Transmission
≥ 90% average (typical)
Surface Quality
80-50 scratch-dig
Thickness
1.1 mm
Thickness Tolerance
±0.1 mm

Clear Aperture
≥90% of filter size with film to the edge
Temperature Range
-100 to 400 º C
Humidity Resistance
MIL-STD-810, Method 507.3, Procedure III, Modified to 40 cycles
Abrasion, Adhesion, Hardness
MIL-C-48497
Cleaning
Non-abrasive method, acetone or isopropyl alcohol on lens tissue recommended

Features

Angle of Incidence Effects

The cut-on wavelength of Newport Stabilife™ Colored-Glass Alternative filters will slightly shift lower in wavelength with an increase in the angle of incident collimated light. The amount of wavelength shift is dependent upon the incident angle and the effective index (ne) of the filter. This feature can be very useful in research applications by being able to custom tune a CGA filter to a specific desired wavelength. The following formula may be used to determine the wavelength shift of a filter in random polarized collimated light:
λ_θ = λ_o [1-(n_o/n_e)² sin²θ]^1/2
where
λ_θ = Cut-on wavelength at θ° angle of incidence
λ_o = Cut-on wavelength at 0° angle of incidence
θ = Angle of incident light off normal incidence
n_o = Effective index of refraction of the environment (n_o = 1 in air)
n_e = Effective index of refraction of the optic; specified as a numerical value derived from the indices of the thin film layers of the CGA filter

specified as a numerical value derived from the indices of the thin film layers of the CGA filter

Cone-Angle Effects

In some applications, the incident light is presented at the filter in a convergent or divergent cone. The cone is made up of many light rays at various angles ranging from normal incidence to the extreme angle defining the full cone. The effect of this collection of rays is a weighted average of incident light, producing a wavelength shift toward shorter wavelengths that is smaller than the shift that would be produced if collimated light was presented to the filter at the extreme angle of the full cone.

Stain Resistance

CGA filters have been evaluated for stain resistance using the Acid Resistance test set forth in ISO 8424. This test is used to determine the surface change that results from exposure to a strong acidic substance. The surface is exposed to a Nitric Acid solution (0.5M/l) having a pH of 0.3 ± 0.05. Testing is conducted to determine the amount of time needed to etch into the surface to a depth of 0.1 µm. Newport's CGA filters have been confirmed to meet an SR1 rating which corresponds to greater than 100 hours of exposure. Since CGA filters are constructed of very thin layers of vacuum-deposited thin-film coating, an etch depth of 0.1 µm would likely result in a significant change in the spectral performance of the filter. No spectral change was evident after testing indicating an absence of any significant etching after the 100 hour exposure.

Abrasion Resistance, Adhesion, & Humidity Resistance

CGA filters have been qualified for adhesion using the snap tape test specified in MIL-C-48497, for abrasion resistance using the eraser test specified in MIL-C-675, and for humidity resistance using the aggravated test specified in MIL-STD-810E. These tests are commonly used as benchmarks for determining the robustness of thin film coatings.

Solubility

The extreme hardness of the Stabilife® coatings used to manufacture Colored-Glass Alternative Filters allows these filters to be subjected to normal and severe weather conditions as well as to the repeated handling and cleaning that is commonplace for filters that are used in a lab environment, without sustaining any surface degradation. Unlike some Colored-Glass Filters that can suffer surface damage from prolonged exposure to rain or submersion in water, CGA filters maintain their clarity and spectral performance under such extreme conditions.

Optical Radiation

Stabilife® coatings used to manufacture our CGA filters have been deployed in applications where they are exposed intense ultraviolet and high energy visible radiation with no change in spectral performance after prolonged exposure. These filters have also been evaluated for Laser Damage Threshold using a frequency-doubled Nd:YAG laser operating at 532 nm with a pulse width of 10 ns and a repetition rate of 20 Hz. Typical damage threshold values exceed 1.0 J/cm² .

Restrictions on Hazardous Substances (RoHS)

Unlike several Yellow, Orange, and Red Colored-Glass filters, Newport's Colored-Glass Alternative filters are fully compliant with RoHS regulations. They do not rely on a exemption and therefore, are not subject to the uncertainty of the review process.

Extreme Temperature

Colored-Glass Alternative filters are qualified for use at continuous operating temperatures between -100°C and +400°C.

Custom Capability

Newport's Colored-Glass Alternative filters were originally developed for custom and OEM applications either as alternatives to a Colored-Glass filter that utilized non-RoHS compliant material in it formulation, as replacements of a Colored-Glass filter that had been discontinued by one of the major Colored-Glass filter manufacturers, or as a new product to fill a gap in the wavelength offering of the major Colored-Glass filter manufacturers. The versatility of our coating processes and equipment support our ability to offer unlimited combinations of wavelength, size, shape, thickness, optical figure, surface quality, etc.. In the table that follows, we have listed some of the principle capability specifications for CGA filters Please provide your detailed requirements to our technical sales team and allow us to engineer the exact solution to meet your application.