{"id":153,"date":"2022-01-04T17:51:51","date_gmt":"2022-01-04T09:51:51","guid":{"rendered":"https:\/\/www.eee.hku.hk\/microLED\/?p=153"},"modified":"2022-01-04T17:51:53","modified_gmt":"2022-01-04T09:51:53","slug":"polychromatic-light-emitting-diodes-with-a-fluorescent-nanosphere-opal-coating","status":"publish","type":"post","link":"https:\/\/www.eee.hku.hk\/microLED\/polychromatic-light-emitting-diodes-with-a-fluorescent-nanosphere-opal-coating\/","title":{"rendered":"Polychromatic light-emitting diodes with a fluorescent nanosphere opal coating"},"content":{"rendered":"\n<p class=\"has-text-align-right\">&#8211; <em>KN Hui, WY Fu, WN Ng, CH Leung, PT Lai, KKY Wong, and HW Choi<\/em><\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"505\" src=\"https:\/\/www.eee.hku.hk\/microLED\/wp-content\/uploads\/2022\/01\/Hui_2008_Nanotechnology_19_355203_sch-1-1024x505.png\" alt=\"\" class=\"wp-image-156\" srcset=\"https:\/\/www.eee.hku.hk\/microLED\/wp-content\/uploads\/2022\/01\/Hui_2008_Nanotechnology_19_355203_sch-1-1024x505.png 1024w, https:\/\/www.eee.hku.hk\/microLED\/wp-content\/uploads\/2022\/01\/Hui_2008_Nanotechnology_19_355203_sch-1-300x148.png 300w, https:\/\/www.eee.hku.hk\/microLED\/wp-content\/uploads\/2022\/01\/Hui_2008_Nanotechnology_19_355203_sch-1-768x379.png 768w, https:\/\/www.eee.hku.hk\/microLED\/wp-content\/uploads\/2022\/01\/Hui_2008_Nanotechnology_19_355203_sch-1-1536x758.png 1536w, https:\/\/www.eee.hku.hk\/microLED\/wp-content\/uploads\/2022\/01\/Hui_2008_Nanotechnology_19_355203_sch-1-2048x1011.png 2048w, https:\/\/www.eee.hku.hk\/microLED\/wp-content\/uploads\/2022\/01\/Hui_2008_Nanotechnology_19_355203_sch-1-500x247.png 500w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><figcaption>Schematic diagram of the fluorescent nanosphere coated<br>device<\/figcaption><\/figure>\n\n\n\n<p><strong><em>Nanotechnology<\/em>, vol.\u00a0<strong>19, 35, pp.<\/strong>\u00a0355203 (2008)<\/strong> <\/p>\n\n\n\n<p>A hexagonally close-packed array consisting of fluorescent nanospheres was coated onto short-wavelength GaN light-emitting diodes to demonstrate polychromatic white light emission. The spherical particles self-assemble into ordered three-dimensional opal structures, performing the role of color conversion to generate a polychromatic spectrum with smooth and uniform emission patterns. Different ratios of green and orange-red fluorescent nanospheres were mixed and coated onto high-extraction-efficiency micro-LEDs. Four devices with different shades of white emission were demonstrated. Device A, with a high content of orange-red nanospheres, offers the highest CRI value of 80, whereas device C with a well-balanced ratio of green and orange-red nanospheres exhibits color characteristics closest to ideal white with CIE coordinate at (0.34, 0.34). At 20\u00a0mA driving current, the luminous efficacy of the devices A, B, C, and D are 40.5\u00a0lm\u00a0W<sup>\u22121<\/sup>, 57.7\u00a0lm\u00a0W<sup>\u22121<\/sup>, 63.1\u00a0lm\u00a0W<sup>\u22121<\/sup>, and 67.2\u00a0lm\u00a0W<sup>\u22121<\/sup>\u00a0respectively, while the correlated color temperatures (CCTs) of the corresponding devices are 3587, 4778, 5271, and\u00a013\u2009000\u00a0K.<\/p>\n\n\n\n<p>DOI:<a href=\"https:\/\/doi.org\/10.1109\/LED.2004.826541\" data-type=\"URL\" data-id=\"https:\/\/doi.org\/10.1109\/LED.2004.826541\"> <\/a><a rel=\"noreferrer noopener\" href=\"https:\/\/doi.org\/10.1088\/0957-4484\/19\/25\/255302\" data-type=\"URL\" data-id=\"https:\/\/doi.org\/10.1088\/0957-4484\/19\/25\/255302\" target=\"_blank\"><\/a><a href=\"https:\/\/doi-org.eproxy.lib.hku.hk\/10.1088\/0957-4484\/19\/35\/355203\" data-type=\"URL\" data-id=\"https:\/\/doi-org.eproxy.lib.hku.hk\/10.1088\/0957-4484\/19\/35\/355203\"><a href=\"https:\/\/doi-org.eproxy.lib.hku.hk\/10.1088\/0957-4484\/19\/35\/355203\">10.1088\/0957-4484\/19\/35\/355203<\/a><\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>&#8211; KN Hui, WY Fu, WN Ng, CH Leung, PT Lai, KKY Wong, and HW Choi Nanotechnology, vol.\u00a019, 35, pp.\u00a0355203 (2008) A hexagonally close-packed array&hellip;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[3],"tags":[7,4],"class_list":["post-153","post","type-post","status-publish","format-standard","hentry","category-publications","tag-color-tuning","tag-microled"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/www.eee.hku.hk\/microLED\/wp-json\/wp\/v2\/posts\/153","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.eee.hku.hk\/microLED\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.eee.hku.hk\/microLED\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.eee.hku.hk\/microLED\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.eee.hku.hk\/microLED\/wp-json\/wp\/v2\/comments?post=153"}],"version-history":[{"count":1,"href":"https:\/\/www.eee.hku.hk\/microLED\/wp-json\/wp\/v2\/posts\/153\/revisions"}],"predecessor-version":[{"id":157,"href":"https:\/\/www.eee.hku.hk\/microLED\/wp-json\/wp\/v2\/posts\/153\/revisions\/157"}],"wp:attachment":[{"href":"https:\/\/www.eee.hku.hk\/microLED\/wp-json\/wp\/v2\/media?parent=153"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.eee.hku.hk\/microLED\/wp-json\/wp\/v2\/categories?post=153"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.eee.hku.hk\/microLED\/wp-json\/wp\/v2\/tags?post=153"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}