Welcome to Optical Comparators blog.

Since 1986 Dorsey Metrology have been manufacturing high quality optical comparators.

You can contact us about optical comparators sales, service and general informaion by calling directly to +1-845-454-3111.

Archive for 'chart'

Optical Comparator Grid Chart Styles

Tables below show available styles for grid  charts for optical comparators made by Dorsey Metrology.

Grid charts styles
Style Magnification Increments
Inches
Style 60 10X .005
Style 61 10X .01
Style 62 20X .0025
Style 63 20X .005
Style 64 31.25X .001
Style 65 31.25X .002
Style 66 31.25X .005
Style 67 62.50X .001
Style 68 50X .001
Style 69 50X .002
Style 70 100X .0005
Style 71 100X .001
Grid charts styles
Style Magnification Increments
Millimeters
Style M60 10X .2
Style M62 20X .1
Style M68 50X .04
Style M70 50X .02

Optical comparator grid and radius chart styles

Dorsey Metrology offers many styles for its optical comparator charts. Tables below show available styles for grid and radius charts.

Grid and Radius charts styles
Style Magnification Increments
Inches
Style 40 10X .005
Style 41 20X .0025
Style 42 31.25X .002
Style 43 50X .001
Style 44 62.50X .001
Style 45 100X .0005
Style 46 20X .002
Style 47 25X .002
Grid and Radius charts styles
Style Magnification Increments
Millimeters
Style M40 10X .2
Style M41 20X .1
Style M42 31.25X .05
Style M43 50X .04
Style M44 62.50X .025
Style M45 100X .02

Optical comparator grid and radius chart

Illustration shows Dorsey’s grid and radius chart. Please contact our sales department at +1-845-454-3111 for ordering information.

optical comparator grid and radius chart
When ordering optical comparator chart, please specify the following:

  • style of chart (more available – images coming soon)
  • type and model of optical comparator
  • lens magnification
  • chart material – glass or plastic
  • additional information required for particular chart or scale

Optical comparator general purpose chart

Illustration below shows one of our optical comparators general purpose glass chart, style 12.

glass chart

To see larger version follow the link glass chart. Illustration is a svg file and can be zoomed in without any loss in quality.

Optical comparator charts

Standard optical comparator charts

Dorsey Metrology uses satin ground glass of superior quality for all our optical comparator glass charts. The charts are very durable and will last for many years with proper care. Glass charts should be cleaned only with mild soap and water solution using soft cotton cloth. Window cleaners, thinners, and alcohol should never be used to clean your glass chart. All optical comparator glass charts are traceable to the N.I.S.T. and are available with certification at no extra cost.

Glass charts are typically required when:

  • The existing chart has been severely chipped or broken
  • The lines on the existing screen have faded or worn off

The new chart will remain in the comparator for an extended period of time.

Optical comparator overlay charts

Overlay charts are made of plastic and are placed over the existing glass screen. They are typically required when charts are interchanged on a frequent basis. Dorsey Metrology offers 4 types of plastic overlay material:

  • .007″ thick clear mylar
  • .007″ thick frosted mylar
  • .050″ thick clear vinyl
  • .050″ thick frosted vinyl

Optical comparator scales

Dorsey Metrology also offers three types of optical comparator scales:

  • inch/decimal
  • decimal/metric
  • multi-magnification

The inch/decimal and decimal/metric scales are available in glass and are useful for sight verification. The multi-magnification scales are useful for direct screen measurements of projected images on a comparator that is not equip with either digital readouts or micrometer readers. These scales are available in glass or 050″ thick vinyl. All optical comparator scales are traceable to the N.I.S.T. Certification sheets specifying traceability are available at no extra cost. Glass scales are available with serialized numbers. All scales are intended for sight verification and not for comparator calibration.

How to order your optical comparator chart?

When ordering your optical comparator chart, please have the following information available:

  • style of chart
  • type of optical comparator and model number
  • lens magnification
  • chart material
  • any additional information required for a particular chart or scale