The collimated beam arc lamp housing produces a collimated 1 inch diameter uniform beam at the exit port. This allows for the attachment of refractive condensing optics (sold separately) to refocus the output light into a very fine focal point for maximum brightness. This is ideal for fiber optic applications where the light needs to be condensed into a small entrance of a fiber bundle. This lamp housing is designed for 75W-200W Xenon, Mercury-Xenon, and Mercury short arc lamps (sold separately). The housing is forced air cooled with the arc lamp mounted in a vertical position. The exit port collects light from the side of the arc lamp with a back mounted spherical reflector to double light collection. Please specify arc lamp wattage and type at time of ordering as the lamp socket and cooling shroud is specific to the selected arc lamp. Optical Configuration The arc lamp is mounted in a vertical position with the exit port on the side wall. A back spherical reflector mounted on adjustable alignment pins redirects the rear illumination to the forward exit port thereby doubling the amount of light collected. This configuration is still not as effective as the ellipsoidal reflector based arc lamp housings (Models 200-100 and 200-1K) system in light collection although it does produce a more uniform beam. Beam Collimation (Parallel Beam) A 1 inch diameter collimating lens (f/1 input) is mounted at the exit port of the arc lamp housing to produce near parallel output rays. This lens is made of BK7 glass and filters most harmful UV rays below 315nm. For UV applications, this lens can be replaced with a fused silica version, at extra cost, which allows all wavelengths including UV light above 200nm to pass through. The lens is mounted 1" from the center of the arc lamp and is in fact located inside the arc lamp housing. The 1" diameter output coupling tube that holds this lens in place protrudes inwards to bring the lens closer to the arc lamp for greater light collection efficiency. Focusing Optics Refractive condensing optics can be attached to the exit port of the Model 201-100 arc lamp housing to focus the light into a fine focal spot. Refractive condensing optics is actually better at condensing light into a smaller spot than ellipsoidal reflector based optics like the Model 200-100 and 200-1K arc lamp housings. More importantly, refractive condensing optics can be set to any aperture value allowing it to better match the f number of the device it is illuminating for maximum light transfer efficiency. Ellipsoidal reflector based optics on the other hand, has a fixed aperture and therefore cannot match the f number of any illuminated device. Air Cooling The collimated beam arc lamp housing has a forced air-cooled fan that draws air from the bottom of the housing and blows it out the top. For Hg and HgXe lamps there is additional shroud to make the housing cooler. For 50W-75W arc lamps, convection cooling maybe sufficient. In this case, the forced air fan unit can even be dismounted. Optical Beam Height The center beam line of the exit port is 136.88mm above the base of the lamp housing. This can be too high for some optical systems. To lower the center beam line, the arc lamp housing can be rotated 90º about its exit port such that it lies horizontally. An optional horizontal mounting bracket is available for this purpose. However, a horizontally operated lamp is not recommended for mercury or mercury-xenon lamps as it shortens the lamp’s service life. Mounting The arc lamp housing has 4 holes on its base plate that can be used for mounting onto an optical table. The holes are spaced 2" apart to match the hole pattern of an imperial (inch) optical table. Alternatively, these mounting holes can be used for placing the optional adjustable height feet for level control if the housing is used on an uneven surface. Supported Arc Lamps This lamp housing supports 75W-200W short arc lamps which are sold separately. Since each arc lamp type and wattage has its own socket style and cooling shroud requirement, it must be specified at the time of ordering. The arc lamp housing will not be able support another type or wattage of arc lamp after it is manufactured. Optical Power Sciencetech has taken broadband measurements of this arc lamp housing with selected arc lamps. For example, a 150W Xe lamp generates approx 1W at the output port. Focusing this into a 1/8" diameter UV quartz fiber bundle reduces it to 250mW at the output end of the fiber bundle. Using a 100W Hg arc lamp, 700mW was recorded at the output port using a broadband thermal detector. Using a 200W HgXe arc lamp, 1.1-1.6W was recorded at the output port (two lamps were measured, one has aged). Focusing this into a 1/8" diameter UV quartz fiber bundle reduces it to 400mW at the output end of the fiber bundle (using new lamp). Please note that these are very rough broadband figures for comparison purposes only as the amount of power also depends on the fiber size and lamp arc gap size. If you are concerned about the light output power, please consult with a Sciencetech Application Specialist for details. Power Supply The Model 201-100 arc lamp housing is designed to work with Sciencetech Model 550-200 adjustable power supply and Model 500-IG igniter (sold separately). This power supply is a highly stabilized linear DC power supply that can be manually adjusted from 0-200W. An optional Optical Feedback Unit (Model FS-02) with a built-in light sensor is available to monitor the light intensity of the arc lamp and automatically adjust the power supply to maintain a consistent non-fluctuating intensity. The Model 201-100 arc lamp housing can also be used with other DC arc lamp power supplies as long as the power supply provides both DC output for lamp and 120VAC output for its cooling fan. The power supply must also have its own arc lamp ignition. Cable Connection There are three cable connections to the arc lamp housing. The positive and negative lamp cables require male Pomona 4986 connectors which plug into the female Pomona 6387-ST-T terminals on the arc lamp housing. The cooling fan requires 120VAC and has a separate Amphenol C16 connector for connection to the Sciencetech Model 550-200 power supply. The arc lamp housing ground follows the cooling fan ground via the Amphenol C16 connector. Other Lamp Housing Models The Model TH3 is the only lamp housing that Sciencetech offers for Quartz Tungsten Halogen lamps. If the user requires more UV light, then Sciencetech's deuterium light sources are recommended. If the user requires a greater broadband ranging from UV to IR, then Sciencetech's arc lamp light sources are recommended. Customization Sciencetech has built many customized versions of the Model TH3 QTH lamp housing. Examples include a water cooled version, a 2 inch diameter output beam version, and a fiber optic illumination version. If you require a certain feature in this QTH lamp housing that is not shown, please contact our Applications Specialists at sales@sciencetech-inc.com for a custom quotation. Technical Specifications

• 1 inch (25mm) diameter exit port, with f/1 collimating lens
• 1-3/8" back spherical reflector to double light output (for both 1" and 2" optics)
• Removable Top for lamp replacement
• Three point adjustable pins for back spherical reflector alignment
• Aluminum body, black anodized
• + and - terminals for arc lamp power (12DC-35DC typical)
• Live and neutral terminals for cooling fan (115-120VAC)
• Distance Center of Lamp to Exit Port: 30mm
• Center Beam Line Height: 5.389" (136.88mm) above the optical table (not including adjustable feet)
• Dimensions: 205.79 x 133.35 x 276.68mm (8.102" x 5.250" x 10.893") (LxWxH)