{"id":25730,"date":"2026-11-10T09:29:10","date_gmt":"2026-11-10T09:29:10","guid":{"rendered":"https:\/\/hlled.com\/?p=25730"},"modified":"2026-11-10T09:34:25","modified_gmt":"2026-11-10T09:34:25","slug":"diffused-vs-clear-cover","status":"publish","type":"post","link":"https:\/\/hlled.com\/de\/comparisons\/diffused-vs-clear-cover\/","title":{"rendered":"Diffused vs Clear Cover: Light Quality and Glare"},"content":{"rendered":"

A clear cover passes most of the light and shows every diode. A diffused cover hides the diodes and gives up part of the output. That is the whole trade in one sentence \u2014 but it is not the sentence that decides most installations. What decides them is what the light lands on<\/strong>, because a clear cover over a polished surface does not just show dots. It shows them twice.<\/p>\n\n\n\n

\"A
The cover determines what leaves the fixture: a spread, a cone, or a row of points.<\/figcaption><\/figure>\n\n\n\n

What does each cover do to the light?<\/h2>\n\n\n\n

Three families, and the transmission figures are typical rather than exact \u2014 they move with material and thickness.<\/p>\n\n\n\n

Cover<\/th>Transmission<\/th>Diode visibility<\/th>Typical use<\/th><\/tr><\/thead>
Clear<\/td>~90\u201395%<\/td>Visible at close range<\/td>Hidden runs, indirect light, lens<\/td><\/tr>
Frosted \/ semi-clear<\/td>~70\u201385%<\/td>Softened, still present<\/td>Task light, mid-range viewing<\/td><\/tr>
Opal \/ milky<\/td>~60\u201370%<\/td>Not visible<\/td>Direct-view lines, polished surfaces<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

The order is not a quality ranking. A clear cover is the correct specification for a cove where the strip is never seen; an opal cover is the correct specification for a kitchen counter you stand at every day. Choosing “the best one” without viewing conditions is how most cover mistakes occur.<\/p>\n\n\n\n

\"PC
The same section, three covers: the difference is how much the diodes blur.<\/figcaption><\/figure>\n\n\n\n

Where do the dots actually come from?<\/h2>\n\n\n\n

Three variables, and the cover is only one of them.<\/p>\n\n\n\n

Diode spacing.<\/strong> A strip with 60 LEDs per meter has gaps between emitters; at 120 or 160 LEDs per meter, the gaps are half or a third as wide. A COB strip has no gaps at all \u2014 it is a continuous phosphor layer.<\/p>\n\n\n\n

Cavity depth.<\/strong> The distance between the diode and the cover allows light from adjacent emitters to overlap before it reaches the surface. A 5 mm cavity has almost no mixing distance; a 15 mm cavity has a lot of mixing distance.<\/p>\n\n\n\n

Cover diffusion.<\/strong> Opal scatters hardest, frosted partially, clear not at all.<\/p>\n\n\n\n

The useful consequence: a shallow body with an opal cover can still show dots, and a deep body with a frosted cover can be clean.<\/strong> Changing the cover without changing the depth often disappoints.<\/p>\n\n\n\n

\"HL-A065
HL-A065 \u2014 15.5 \u00d7 12.5 mm. A shallow body leaves little distance for the light to mix.<\/figcaption><\/figure>\n\n\n\n

Why does a clear cover fail over polished stone?<\/h2>\n\n\n\n

Because the surface becomes a second light source.<\/p>\n\n\n\n

A clear cover transmits the diodes almost unchanged, so the fixture is, optically, a row of point sources. Put that above polished granite, glazed tile, or a lacquered counter, and the surface reflects each point at the viewer. You do not see one row of dots \u2014 you see the row and its reflection, offset, at twice the apparent density.<\/p>\n\n\n\n

This is the single most common complaint after a retrofit, and it is not a defect in the cover. It is a cover chosen for the wrong surface.<\/p>\n\n\n\n

Two ways out: an opal cover (which removes the point sources), or a high-density or COB strip (which removes the gaps). Doing neither leaves a line that looks wrong from every standing position.<\/p>\n\n\n\n

When is a clear cover the right answer?<\/h2>\n\n\n\n

Four cases, all of which share one property: the strip is not in the line of sight.<\/p>\n\n\n\n