Peak #1990 Anastigmatic Loupe [film viewer]+

This anastigmatic loupe is incomparable to any other produced. The high precision PEAK magnifier, either with 4x or 7x magnification, has been specifically made for the professional user to view the complete microfilm size (here, the 4x) 32 mm x 45 mm) or flat objects less than 58 mm in diameter.

The special glass lens produces a very high contrast image, which remains sharp and undistorted throughout the whole viewing field to the edges. The Achromatic lens is superior in providing a fully true color corrected image. All this, combined with the lenses anti-reflection coating, gives any micro-film-viewer the full advantage of a crystal clear image.

You can focus your image by using the very finely adjusted focusable ring. A crosshair metric scale reticule is included in both versions and can be easily installed or removed when needed. The metal housing has a transparent base which permits incident and transmitted light.

While the 4x magnification has been made to view the full film, the 7x magnification has been designed for the user who needs to inspect certain parts of the film in much finer detail.

Specifications:

2804151

• Field of View: 59 mm
• Working distance: 54 mm

• Aperture: 30 mm
• Min scale division: 0.1 mm, 60 mm length

• Size: 73 x 77 mm
• Weight: 272 grams

2807155

• Field of View: 40 mm
• Working distance: 36 mm

• Aperture: 22 mm
• Min scale division: 0.1 mm, 40 mm length

• Size: 55 x 53 mm
• Weight: 103 grams

Chromatic aberration is caused by a lens having a different refractive index for different wavelengths of light (lens dispersion), meaning that different colors focus at different distances from the lens. Longitudinal and lateral chromatic aberration of a lens can be seen as "fringes" of color around the image.

Chromatic aberration of a single lens causes different wavelengths of light to have differing focal lengths.

An achromatic doublet has the same focal length for red and blue light.

Chromatic aberration can be minimized by using an Achromatic Lens or Achromat, in which special optical materials with differing dispersion are assembled together to form a compound lens.