2a:null 2b:["$","title",null,{"children":"Wavelengths and Spectral Colours | Marcus A. Gordon | Observable"}] 30:T740,// takes wavelength in nm and returns an rgba value function wavelengthToColor(wavelength) { let R, G, B, alpha, colorSpace, wl = wavelength, gamma = 1; if (wl >= 380 && wl < 440) { R = -1 * (wl - 440) / (440 - 380); G = 0; B = 1; } else if (wl >= 440 && wl < 490) { R = 0; G = (wl - 440) / (490 - 440); B = 1; } else if (wl >= 490 && wl < 510) { R = 0; G = 1; B = -1 * (wl - 510) / (510 - 490); } else if (wl >= 510 && wl < 580) { R = (wl - 510) / (580 - 510); G = 1; B = 0; } else if (wl >= 580 && wl < 645) { R = 1; G = -1 * (wl - 645) / (645 - 580); B = 0.0; } else if (wl >= 645 && wl <= 780) { R = 1; G = 0; B = 0; } else { R = 0; G = 0; B = 0; } // intensty is lower at the edges of the visible spectrum. if (wl > 780 || wl < 380) { alpha = 0; } else if (wl > 700) { alpha = (780 - wl) / (780 - 700); } else if (wl < 420) { alpha = (wl - 380) / (420 - 380); } else { alpha = 1; } colorSpace = ["rgba(" + (R * 100) + "%," + (G * 100) + "%," + (B * 100) + "%, " + alpha + ")", R, G, B, alpha] // colorSpace is an array with 5 elements. // The first element is the complete code as a string. // Use colorSpace[0] as is to display the desired color. // use the last four elements alone or together to access each of the individual r, g, b and a channels. return colorSpace; }31:[] 2e:{"id":"1b3c289f30bceace","slug":"wavelengths-and-spectral-colours","title":"Wavelengths and Spectral Colours","thumbnail":"94b66d75fd67b3e71a7e6732d02f832c2e733f9b08ee01f8e83001031afd4475","access_level":"public","create_time":"$D2018-12-06T02:07:41.382Z","update_time":"$D2024-06-28T22:54:02.767Z","view_time":null,"first_public_time":"$D2018-12-09T19:38:07.043Z","has_unpublished_edits":null,"fork":false,"stars":6,"starred":false,"owner":{"type":"team","id":"4b22c05d2e5d88fa","login":"magfoto","name":"Marcus A. Gordon","avatar_url":"https://avatars-next.observableusercontent.com/62af054df1febace05e62325fb1033c100accaf22fa9ac560aa466aaabcc0f96","tier":"starter_2024"},"version":346,"publish_version":346,"role":null,"authored":false,"authors":[{"type":"individual","id":"1b92bb55c093434d","login":"magfoto","name":"Marcus A. Gordon","avatar_url":"https://avatars-next.observableusercontent.com/a0eddd158dd4bd2dcc0e776652fc507eee01886e26ecd85028410f8bd163e86e","tier":null}],"members":[{"type":"individual","id":"1b92bb55c093434d","login":"magfoto","name":"Marcus A. Gordon","avatar_url":"https://avatars-next.observableusercontent.com/a0eddd158dd4bd2dcc0e776652fc507eee01886e26ecd85028410f8bd163e86e","tier":null,"role":"editor"}],"comments":[],"custom_thumbnail":false,"trashed":false,"lapsed":null,"subscribed":null,"forks":1,"collection":{"id":"261e14106527de33","slug":"holography-notebook","title":"Holography Research","owner":{"id":"4b22c05d2e5d88fa","login":"magfoto","name":"Marcus A. Gordon"}},"type":"notebook","body":{"titling":"auto","title":"Wavelengths and Spectral Colours","cells":[{"id":0,"value":"md`# Wavelengths and Spectral Colours`","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","providerMetadata":"$undefined","attachments":"$undefined","output":"$undefined","database":"$undefined"},{"id":112,"value":"md `Wavelength (nm) range of visible spectrum, with a floating point RGB converted value.`","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","providerMetadata":"$undefined","attachments":"$undefined","output":"$undefined","database":"$undefined"},{"id":40,"value":"viewof x = {\n const div = html`\n \n nanometres (nm)\n`;\n const range = div.querySelector(\"[type=range]\");\n const number = div.querySelector(\"[type=number]\");\n div.value = range.value = number.value = 400;\n range.oninput = () => number.value = div.value = range.valueAsNumber;\n number.oninput = () => range.value = div.value = number.valueAsNumber;\n return div;\n}","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","providerMetadata":"$undefined","attachments":"$undefined","output":"$undefined","database":"$undefined"},{"id":86,"value":"html`

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`","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","providerMetadata":"$undefined","attachments":"$undefined","output":"$undefined","database":"$undefined"},{"id":100,"value":"md `__Wavelength__: ${x.toFixed(1)} nm| __${tex`\\lambda`}__: ${x.toFixed(0) / 1000} ${tex`\\mu`} (microns) | __RGB__: (${wavelengthToColor(x)[1].toFixed(2)}, ${wavelengthToColor(x)[2].toFixed(2)}, ${wavelengthToColor(x)[3].toFixed(2)})`","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","providerMetadata":"$undefined","attachments":"$undefined","output":"$undefined","database":"$undefined"},{"id":106,"value":"html `

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