{"id":389626,"date":"2024-10-15T09:00:33","date_gmt":"2024-10-15T09:00:33","guid":{"rendered":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/fdtd-far-field-projection-error\/"},"modified":"2024-10-15T09:00:33","modified_gmt":"2024-10-15T09:00:33","slug":"fdtd-far-field-projection-error","status":"publish","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/fdtd-far-field-projection-error\/","title":{"rendered":"FDTD far-field projection error"},"content":{"rendered":"<p>&lt;p&gt;<img decoding=\"async\" src=\"https:\/\/innovationspace.ansys.com\/forum\/wp-content\/uploads\/sites\/2\/2024\/10\/15-10-2024-1728982249-untitled.png\" alt=\"\" \/><img decoding=\"async\" src=\"https:\/\/innovationspace.ansys.com\/forum\/wp-content\/uploads\/sites\/2\/2024\/10\/15-10-2024-1728982771-mceclip2.png\" \/>&lt;\/p&gt;&lt;p&gt;<img decoding=\"async\" src=\"https:\/\/innovationspace.ansys.com\/forum\/wp-content\/uploads\/sites\/2\/2024\/10\/15-10-2024-1728982505-mceclip1.png\" \/>&lt;\/p&gt;&lt;p&gt;I&#8217;m working in to simulate the far-field scattering pattern of 10x10um substrate with ultra-transparent(T~0.92) thin film(~100nm).&nbsp;&lt;\/p&gt;&lt;p&gt;When I using the far-field &lt;span class=&#8221;notion-enable-hover&#8221; data-token-index=&#8221;0&#8243;&gt;projections property of DFT monitor, there are some awkward Moire pattern is appeared.&lt;\/span&gt;&lt;!&#8211; notionvc: d7a27a48-bac9-405a-8c5b-babd558996e9 &#8211;&gt;&lt;\/p&gt;&lt;p&gt;I&#8217;m not sure exactly what causes the above pattern to appear. I have tried changing the monitor&#8217;s position and the mesh size, but it was of little use. The attached photo shows the result observed with a monitor placed 0.5 &micro;m away from the film surface using a 10 nm mesh.&lt;\/p&gt;&lt;p&gt;The only way to suppress this pattern was by reducing the Gaussian beam waist from 3\u202f&micro;m to 1\u202f&micro;m (right side of image). Could you please explain exactly what causes this pattern and advise on how to resolve it?&lt;\/p&gt;&lt;p&gt;&lt;span class=&#8221;notion-enable-hover&#8221; data-token-index=&#8221;0&#8243;&gt;Sincerely.&lt;\/span&gt;&lt;\/p&gt;&lt;p&gt;&nbsp;&lt;\/p&gt;&lt;p&gt;&nbsp;&lt;\/p&gt;<\/p>\n","protected":false},"template":"","class_list":["post-389626","topic","type-topic","status-publish","hentry","topic-tag-fdtd"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_author_ip":["143.248.111.77"],"_btv_view_count":["161"],"_bbp_topic_status":["unanswered"],"_bbp_subscription":["2592"],"_bbp_topic_id":["389626"],"_bbp_forum_id":["27833"],"_bbp_engagement":["2592","426100"],"_bbp_voice_count":["2"],"_bbp_reply_count":["1"],"_bbp_last_reply_id":["390078"],"_bbp_last_active_id":["390078"],"_bbp_last_active_time":["2024-10-16 15:45:35"]},"test":"minki99kaist-ac-kr"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/389626","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics"}],"about":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/types\/topic"}],"version-history":[{"count":0,"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/389626\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=389626"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}