输入光学元件
光测量单位依据特定的空间响应特性而定义，确保测量精度则离不开精心设计的输入光学系统。
在辐射度学与光度学中，两大几何光学定律发挥着直接作用：反平方定律与余弦定律。
反平方定律阐述了点光源辐照度与测量表面距离之间的量化关系，即单位面积上的光强与光源至表面距离的平方成反比。
具体而言，若在某点1米处测得辐照度为16 W/cm²，则在距离加倍至2米时，辐照度将减至4 W/cm²，同理可推算出任意距离下的辐照度。进行精确插值的前提是，测量平面需明确界定，且光源需近似于点光源。
在辐射亮度测量（单位：W/cm²/sr）中，当探测器以窄视角观测大面积且均匀的光源时，随着探测器距离的增大，其视野内的光源面积亦随之扩大，这一效应抵消了反平方定律的影响，使得测量结果不再受距离变化的影响。
辐射亮度测量技术对于评估大面积光源（如阴极射线管（CRT）、背光显示器等）或漫反射、均匀照明的表面具有重要意义。
余弦定律则揭示了表面辐照度与入射角之间的关联。随着入射角的增大，有效表面积减小，导致光强按入射角的余弦值比例下降。
对于辐照度与照度探测器，尤其是那些通过滤波器限制非直射光的探测器而言，进行余弦校正至关重要，以确保能够准确量化来自各个角度的光照。不精确的余弦响应是全浸没应用中误差的主要来源之一。
在光测量领域，众多应用场合均需采用专门设计的输入光学元件。例如，强烈的激光束需经过扩散处理，以避免因光束过窄而导致接收器局部饱和。同时，许多高强度紫外光源则需配备耐高温的远程光学元件，这些元件需具备余弦空间响应特性及侧视功能。
以下表格列出了我们的标准输入光学元件产品。若您对我们的光学元件有任何疑问，或需帮助选择适合您应用的光学元件、了解价格信息、或寻求定制解决方案，请通过此处或页面的表单与我们取得联系。
| Image | Part Number | Specifications |
|---|---|---|
| Click to see larger image | ||
Diffusers | Diffusers are used to improve the spacial response of detectors with the goal of creating a cosine corrected response. | |
| PD | Polycarbonate Domed diffuser for VIS applications, 400 - 700 nm, 42 mm diameter OD |
 | W | Quartz (1.024" dia) Wide eye diffuser with internal dome, 200 - 2100 nm, 42 mm diameter OD |
| WU | ^W diffuser with sealant and orings to allow submersion in liquids. 42 mm diameter OD | |
 | TD | Teflon (21.5 mm dia) Dome diffuser 200 - 700 nm, 42 mm diameter OD |
| QT | Teflon (.43” dia.)diffuser with protective quartz window 200-700 nm, 42 mm diameter OD | |
 | QT-#mm | ^QT diffuser with aperture to measure smaller light spots. Available with 1, 3, 5 or 7 mm apertures, 200-700 nm |
 | A313 | Quartz (.43" dia) flat multi-layer diffuser, 200 - 2100 nm, 42 mm diameter OD |
 | A313-#mm | ^A313 diffuser with aperture to measure smaller light spots. Available with 1,3,5 or 7 mm apertures, 200-2100 nm |
 | T | Teflon (.5" dia) diffuser in threaded filter ring. Has mating threads on both sides to allow additional optical components to attach. 42 mm diameter OD |
 | RAA4* | Right-Angle Adapter/Diffuser (.27" dia) with mini integrating sphere .61" dia x .44" tall |
| RAA4X* | Right Angle Adapter /Diffuser (.27” dia )with x10 attenuation, mini integrating sphere .61” dia by .44” tall | |
 | RAA5* | Mini Right Angle Adapter/Diffuser (.25" dia) with internal integrating sphere (.46 x .47 x .84") |
 | A2* | Silica chips in a filter ring to be combined with W or WU for use on Fiber optics (requires MPS2354P2XD to connect to fiber) |
 | W5E* | Miniature cosine correcting diffuser with 6.35 mm OD and ~10.92 mm length. Threads directly on to SMA905 fiber |
| *designed for connection to SMA905 fiber optics/patch cords | ||
Laser Power Adapters | Used for testing small spots of light and or collimated beams | |
 | HNK15 | Narrow beam adapter, eliminates alignment errors. 15 mm opening |
 | K15 | 15 mm aperture and targeting aid |
| K9 | 9 mm aperture and targeting aid | |
Fiber Optics / Patch Cords | Light guides used to connect input optics to sensors/spectrometers with SMA905-SMA905 adapters (unless otherwise noted.) . The tip of the fiber can also be used as an input optic receiving light based on the numerical aperture. | |
 | FFO600SC | 1m 600µm solid core, low solar, Fiber, Patchcord, Kevlar Jacket |
| FFO600FCPC | 1m 600µm solid core, low solar, Fiber, Patchcord, Kevlar Jacket. FCPC to SMA905. | |
| FFO600SCW-3 | Fiber, Kevlar jacket, 3m 600um Solid, submersible, detachable | |
| FFOSMA2UV1000 | SMA2/UV1000/1100N/SQLK6.0mm/2 Fiber Optic, UV 1000/1100 nm | |
| FFO400UVIR | Fiber, 400um, SMA905, BX, 1m 250-2500 nm | |
| FFO2501 | Bndl-0.5m-56x200/220/245 LSHOH sealed at both ends for water immersion; 200 deg C max operating temperature | |
 | FFO12-S | Solid Tubing, rated 300 deg C Fiber Optic, Rigid, 12" L |
| FFO18-S | Solid Tubing, Rated 300 deg C Fiber Optic, Rigid,18" L | |
| P11-2 | Fiber, 600 micron LSHOH, 1.97" | |
| P11-4 | Fiber, 600 micron LSHOH, 3.97" | |
 | PIN4 | Contact Luminance Probe Solid 1000 um, .22NA fiber optic light guide in protective metal tube for remote end-on viewing (SMA905 - Ferrule tip). Requires P6/SMA adapter to mount to ILT detectors and luminance calibration for contact luminance measurements in cd/m2 or fL. (Custom lengths available) |
Filter Rings | Used to mount customers filters to ILT light sensors and spectrometers | |
 | A310 | Mounts filters 25 mm dia., up to 7 mm thick, has 1 ¼"-24 threads |
| A311 | Mounts filters 25 mm dia., up to 4 mm thick, has 1 ¼"-24 threads | |
| MPS235600XD | Mounts filters 12.7 mm dia., up to 4 mm thick, has 1 ¼"-24 threads | |
| MPS235500XD | Mounts filters 12.7 mm dia., up to 7 mm thick, has 1 ¼"-24 threads | |
Right Angle Probe | Used to access light in hard to reach/hostile environments. Withstands exposure to high temperatures and intense UV. | |
 | RAMP12 | Right Angle Mocro Probe FFO12/RAA5. High temperature right angle probe for insertion into harsh environments or remote locations. Withstands temperatures up to 300 deg C. Connects to ILT spectrometers and SED(SEL) version detectors with SMA905 adapters. (P6/SMA sold separately) |
| RAMP18 | Right Angle Mocro Probe FFO18/RAA5 High temperature right angle probe for insertion in harsh environments or remote locations. Withstands Temperatures up to 300 Deg C. Connects to ILT spectrometers and SED(SEL) version detectors with SMA905 adapters. (P6/SMA sold separately) | |
Hoods | Ambient light blocking adapters /occlusion hoods | |
 | H | Hood, internally baffled to reduce stray light and field of view. Accepts standard input optics and filters. Best for distance 25' or less |
| H2 | Occlusion hood with internal surface painted flat black to minimize internal reflections for beam candela measurement on small light sources | |
Lenses | Lenses are often used to create a narrow field of view for luminance/radiance measurements | |
 | L30-1 | High Gains Lens increases detector sensitivity while limiting acceptance angle for visible and near IR applications. For effective intensity of flash sources at a distance greater than 25 feet. (L30-1 must be used with 1 or 2 filters or empty filter rings to assure the lens is at the correct distance from the sensor) |
 | R | Radiance/luminance lens produce an average field of view of +/- 0.75 degree (1.5 degree total) for radiance/luminance measurement of extended sources |
| R1.7 | Radiance/luminace lens use to create 1.7 MRAD | |
| R11 | Radiance/luminace lens use to create 11 MRAD | |
 | R2* | Radiance/luminace lens produce an average field of view of 2 degrees, for radiance/luminance measurement of extended sources |
 | R3* | Small Spot, fixed (500 mm) distance radiance/luminance lens |
| * indicates for use with a fiber optic/patch cord with SMA905 adapter | ||
Adapters | Can be used for alignment, as apertures or for connection of fiber optic light guides | |
 | P2 | Adapter, 4.3 mm I.D. |
| P6 | Adapter, 12.5 mm | |
 | P6/SMA* | Adapter, SMA905 connection |
| * indicates for use with a fiber optic/patch cord with SMA905 adapter | ||
Apertures | Used to reduce a sensor surface area to allow irradiance measurement of small spot of light. Can also be used in place of, or along with neutral density filters to allow measurement of more intense light sources. Apertures can be sold alone, Mounted in a filter ring or combined with filters and optics | |
| 1 mm-7 mm | SHM30727P## apertures with openings 1, 2, 3, 3.2, 4.3, 5 and 7 mm | |
Integrating spheres | Integrating spheres are used to capture the light coming from a source in all directions to allow measurements of total flux (Watts/Lumens) | |
 | INS50* | Integrating Sphere, 2" , .276 “ input port plus 1 SMA905 port to attach fiber optic |
 | INS125 | Integrating sphere, 5" three port - two 20 mm, one 40 mm dia. |
| * indicates for use with a fiber optic/patch cord with SMA905 adapter | ||
