Defocus aberrationvs spherical

This Blacklight/UV light is perfect for bringing out fluorescent properties such as those in our Radium or Uranium element cubes. Shortwave is also preferable to longwave LED blacklights.

Next: 4.2.2 Power Series Representation Up: 4.2 Lens Aberrations and Previous: 4.2 Lens Aberrations and Heinrich Kirchauer, Institute for Microelectronics, TU Vienna 1998-04-17

Defocus aberrationastigmatism

It’s great, I’ve used it to identify sulfur tufts but also just for fun around the house. It’s interesting to see what glows.

4.2.1 Defocus The simplest and most basic aberration type is defocus caused by a wrong vertical position of the image plane. As discussed in Chapter 2 the depth of focus is directly related to the wavelength and the squared reciprocal numerical aperture (cf. (2.2)). In sub-micrometer high-numerical aperture lithography the range over which the image is adequately sharp is typically less than one micron. Thus it is extremely difficult to provide an exact positioning across the entire image field. Problems such as wafer non-flatness, auto-focus errors, leveling errors, lens heating, etc. arise. In case of a positioning error the plane waves do not converge at the wafer. The optical path difference depends on the orientation of the incident rays. The aberration function describing defocus follows from the plane wave decomposition (4.55) and writes to   (4.61) whereby iz, nm = is the vertical component of the wavevector. The paraxial approximation valid for almost vertical incident rays, i.e., ix, n, iy, m 1, yields the simpler relation       (4.62) which will subsequently be used to study the impacts of higher-order aberration types. The obvious effect of defocus is a vertical shift of the focal point above or below the Gaussian image point depending on the sign of . However, if varies across the lens field, the surface of best imagery is not planar and the usable depth of focus is correspondingly reduced [116]. Next: 4.2.2 Power Series Representation Up: 4.2 Lens Aberrations and Previous: 4.2 Lens Aberrations and Heinrich Kirchauer, Institute for Microelectronics, TU Vienna 1998-04-17

Defocus aberrationtest

In case of a positioning error the plane waves do not converge at the wafer. The optical path difference depends on the orientation of the incident rays. The aberration function describing defocus follows from the plane wave decomposition (4.55) and writes to   (4.61) whereby iz, nm = is the vertical component of the wavevector. The paraxial approximation valid for almost vertical incident rays, i.e., ix, n, iy, m 1, yields the simpler relation       (4.62) which will subsequently be used to study the impacts of higher-order aberration types. The obvious effect of defocus is a vertical shift of the focal point above or below the Gaussian image point depending on the sign of . However, if varies across the lens field, the surface of best imagery is not planar and the usable depth of focus is correspondingly reduced [116]. Next: 4.2.2 Power Series Representation Up: 4.2 Lens Aberrations and Previous: 4.2 Lens Aberrations and Heinrich Kirchauer, Institute for Microelectronics, TU Vienna 1998-04-17

365nm Wavelength - This wavelength is perfect for illuminating minerals, insects, bodily fluids, etc.! This light is incredibly fun, not just for illuminating our autunite or radium samples, but also for finding random materials that fluoresce. The light is manufactured with a durable aluminum housing and has a maximum power output of 20 watts.