Variable microinspection system system125
Variable micro-inspection system Characteristics Large fields, high NA The variable microinspection system mag.x system125 stands out from conventional LD inspection systems by virtue of its low overall magnifications that transmit large object fields in high quality. This is achieved through numerical aperture (NA) values far higher than those of other systems. High optical quality is not only ensured on the optical axis, but also is maintained over the entire sensor format. With the tube lens 2.25x, sensor formats up to 56mm are supported. Long distance lenses Thanks to long working distances and correction of the lenses without cover glasses, this system can be universally employed in technical inspection applications. The parfocal distance of the lenses is 125mm. Object space telecentricity Exact object space telecentricity is precisely maintained, preventing flawed measurement results resulting from deep objects or because a variation in object position.
Coupled illumination The high quality of the optical image can only be fully exploited if the object illumination is optimally adjusted. This is why mag.x system125 has a built-in coupled illumination beam path (vertical illuminator) for epi-brightfield illumination. The illumination system operates on the Kohler principle, with adjustable aperture and field stops. Thus the illumination and coherence parameters of the image (relationship of illumination and imaging aperture) can be appropriately adjusted for individual inspection tasks. Fur thermore, the pupil position can be adjusted to the particular lens used, ensuring the optimum telecentric illumination for any lens. Chromatic correction The optics are highly chromatically corrected in the spectral range of 430 700nm (up to 400 800nm, depending on device configurations). The contrast is maintained over the entire spectrum; no re-focusing is required. Modular system The system can be modular modified for adaptation to the customer s exact requirements. Changing individual components is an highly timesaving alternative to developing a new system.
Variable micro-inspection system Schematic drawing of the system Tube system Polarizing filter, rotatable Polarizing filter, rotatable Filter Turret Light guide adapter Illumination unit Objective Specifications Magn. / NA Objective Plan Apochromat Tube Lens System 0.5x 1x 2.25x f tub = 125mm f tub = 250mm f tub = 563mm 2y = 12.5mm 2y = 25mm 2y = 56.25mm WD f obj δ R 0 2y R 0 2y R 0 2y R 0 mm mm µm lp/mm M mm NA lp/mm M mm NA lp/mm M mm NA lp/mm 2x / 0.08 24.8 125.0 ± 42.7 293 1.0 12.5 0.080 293 2.0 12.5 0.040 147 4.5 12.5 0.018 65 5x / 0.20 13.0 50.0 ± 6.8 733 2.5 5.0 0.080 293 5.0 5.0 0.040 147 11.25 5.0 0.018 65 1x / 0.04 250.0 ± 170.6 147 0.5 25.0 0.080 293 1.0 25.0 0.040 147 2.25 25.0 0.018 65 8x / 0.32 31.3 ± 2.7 1172 4.0 3.1 0.080 293 8.0 3.1 0.040 147 18.0 3.1 0.018 65 NA: Object space Numerical Aperture NA : Image space Numerical Aperture WD: Working distance f obj : Focal length of objective lens f tub : Focal length of tube lens system δ: Diffraction limited depth of focus at 546nm, δ = ±n λ /(2 NA 2 ) R 0 : Cut-off frequency in object space at 546nm, R 0 = (2 NA) / λ R 0 : Cut-off frequency in image space at 546nm 2y: Field of view 2y : Image field (maximum detector diagonal) M: Total system magnification in preparation
Performance The following graph displays the optical performance of the mag.x system125 microinspection system, showing the polychromatic MTF versus field height. Values for image and object heights are given under the horizontal axis. Note that the high contrast values close to the diffraction limit are maintained over the entire field! MTF 1 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 R=100 lp/mm R =9 lp/mm R=300 lp/mm R =27 lp/mm R=500 lp/mm R =44 lp/mm y= 0 0.5 1.0 1.5 2.0 2.5 y = 0 5.6 11.3 Feldhöhe16.9 22.5 28.1 Field height Polychromatic MTF vs. field height LD Plan Apo 5x/0.2 + TL2.25x 2y=5 mm, 2y =56.3 mm Applications The usage of high resolution large-format detectors speed up the inspection process. Extremely sensitive line scan sensors, up to 56mm long, enable manufacturers to inspect large areas at high speed, significantly increasing thoughput. Optimally adjusted Kohler illumination highlights even the smallest defects. The excellent optical performance is sustained all the way to the image edge, so that the complete sensor length can be utilised. A telecentric object space beam path means that the optics can also be used for measurement tasks. Careful optimisation of the lenses for the greatest possible working distances affords maximum flexibility in daily production monitoring. With this system, small detectors with sensor diagonals of 2/3 inch and resolutions of over 10 megapixels can be exploited over the entire sensor range. Pixel sizes of around 1.7μm are no problem. Ideal areas of application: Semiconductor industry Flat panel inspection OLED inspection Packaging Photovoltaic and solar panel inspection Universities, laboratories Technical microscopy
Discover the Q! Discover the capabilities, knowledge, equipment and technology of Qioptiq Photonics for Innovation For technical information contact: Qioptiq Photonics GmbH & Co.KG Jan Förster Königsallee 23 37081 Göttingen Direct: +49 (0)5 51 / 69 35-143 Main: +49 (0)5 51 / 69 35-0 Fax: +49 (0)5 51 / 69 35-166 jan.foerster@qioptiq.de www.qioptiq.com