{"id":384,"date":"2020-12-29T18:33:29","date_gmt":"2020-12-29T07:33:29","guid":{"rendered":"http:\/\/www.vk1zdj.net\/?p=384"},"modified":"2023-01-27T10:22:43","modified_gmt":"2023-01-26T23:22:43","slug":"what-is-a-monochromator","status":"publish","type":"post","link":"http:\/\/www.vk1zdj.net\/?p=384","title":{"rendered":"What is a Monochromator"},"content":{"rendered":"\n

On the local amateur radio reflector recently there was an interesting discussion about a Monochromator which was being sold at the local auction place. I spent a bit of time working as a Technical Officer in the Chemistry lab at the Australian Defence Force Academy, so I had seen similar equipment being used for Gas Chromatography, so I decided to pick it up as they are beautiful pieces of optical measurement equipment.<\/p>\n\n\n\n

As I suspected, it is an optical\/mechanical system, based on clever use of mirrors and diffraction gratings, that allows you to focus on a specific wavelength of light from a source. A moveable component allows the diffraction grating to be moved relative to the incoming light source, allowing light only at the desired wavelength to exit the device.<\/p>\n\n\n\n

A scale on the face allows the wavelength of light being passed through to be determined. The scale is measured in ‘mu’ meters (Milli Micro). We use the term nanometres now.<\/p>\n\n\n\n

I used a cheap LED torch, which is predominantly white as the input light to see what the output looked like.<\/p>\n\n\n\n

\"\"<\/p>\n\n\n\n

<\/p>\n\n\n\n

Here is predominantly Green output (540 nm)<\/p>\n\n\n\n

\"\"<\/a><\/figure><\/div>\n\n\n\n

And Red (620 nm)<\/p>\n\n\n\n

\"\"<\/a><\/figure><\/div>\n\n\n\n

And Blue (450 nm)<\/p>\n\n\n\n

\"\"<\/a><\/figure><\/div>\n\n\n\n

If you place a light meter on out output, you can measure the relative intensity of output vs wavelength, allowing one to plot the spectral output of the light source being measured.<\/p>\n\n\n\n

An interesting feature of this particular device, is that it doesn’t pass the output through a single slit. This allows actual images to be examined at particular wavelengths. Using the power of a modern PC LCD screen couples with careful placement of a camera phone, you can see the image of the search bar of my laptop at the wavelength of 618nm.<\/p>\n\n\n\n

\"\"<\/a><\/figure><\/div>\n\n\n\n

In all, a fun little piece of test gear, for wavelengths far shorter than we would normally be playing at within the Amateur bands.<\/p>\n\n\n\n

<\/p>\n","protected":false},"excerpt":{"rendered":"

On the local amateur radio reflector recently there was an interesting discussion about a Monochromator which was being sold at the local auction place. I spent a bit of time working as a Technical Officer in the Chemistry… <\/p>\n","protected":false},"author":1,"featured_media":377,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"inline_featured_image":false},"categories":[18],"tags":[],"jetpack_featured_media_url":"http:\/\/www.vk1zdj.net\/wp-content\/uploads\/2020\/12\/Face.jpg","_links":{"self":[{"href":"http:\/\/www.vk1zdj.net\/index.php?rest_route=\/wp\/v2\/posts\/384"}],"collection":[{"href":"http:\/\/www.vk1zdj.net\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.vk1zdj.net\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.vk1zdj.net\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/www.vk1zdj.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=384"}],"version-history":[{"count":2,"href":"http:\/\/www.vk1zdj.net\/index.php?rest_route=\/wp\/v2\/posts\/384\/revisions"}],"predecessor-version":[{"id":387,"href":"http:\/\/www.vk1zdj.net\/index.php?rest_route=\/wp\/v2\/posts\/384\/revisions\/387"}],"wp:featuredmedia":[{"embeddable":true,"href":"http:\/\/www.vk1zdj.net\/index.php?rest_route=\/wp\/v2\/media\/377"}],"wp:attachment":[{"href":"http:\/\/www.vk1zdj.net\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=384"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.vk1zdj.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=384"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.vk1zdj.net\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=384"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}