Talk:Opto-isolator

Slotted/reflective optocouplers

As I understand it, photointerrupters (transmissive photosensors) and photoreflectors (reflective photosensors) are sometimes referred to as slotted and reflective optocouplers, respectively. They are used to build incremental optical rotary encoders; these, again, are used in ball-type computer mice. However, these things are not what one would usually think of when talking about an optocoupler or optoisolator. Until someone finds the time to explain this properly (sorry, I don't have it right now), the sections referring to these topics are simply confusing. I have therefore removed them from the article and put them here:

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Several types of opto-couplers. The top left and far right detect the presence of an object in between them. They are interruptible. The middle one detects reflections from objects in front of it. The two on the bottom left are both opto-isolators.

• The classical ball computer mouse is a common application, using infrared emitter LEDs and phototransistors to form optocouplers. The ball of the mouse turns a pair of optical encoder wheels. These wheels periodically block the optocouplers and thereby translate the motion of the mouse into a sequence of pulses. These pulses are then used to record the motion. The principle of operation does not require infrared light, but the infrared sensor is less sensitive to interference from common flickering visible light sources such as fluorescent lamps and CRT displays.

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--128.130.60.86 11:35, 26 September 2007 (UTC)

Schematic

This article could use an image of the schematic representation of an opto-isolator to better get the point across.--Hooperbloob 01:20, 8 Jun 2005 (UTC)

How about a circuit? - Omegatron 14:53, Jun 8, 2005 (UTC)

• Hey, that looks great. If some part identifiers are added then we can reference them in the discussion.--Hooperbloob 16:37, 8 Jun 2005 (UTC)

Ok. I did it right, right? Output will be high or low depending on switch. - Omegatron 17:43, Jun 8, 2005 (UTC)

Added some ugly numbers. - Omegatron 14:27, Jun 15, 2005 (UTC)

Merge with Optical isolator

These two articles seem to cover the same thing. -- Bob Mellish 18:45, 7 October 2005 (UTC)

agreed. — Omegatron 15:04, 4 November 2005 (UTC)

Comments

There should be some discussion on analog versus digital isolation. Efadae (talk) 21:33, 17 April 2009 (UTC)

Dead Link

The link to one of the pdf's listed on the bottom of the page is dead. —Preceding unsigned comment added by 212.37.244.183 (talk) 10:05, 17 June 2009 (UTC)

The link http://www.radiation-effects.com/pdf/RLAT.pdf is still dead today 11 nov 2009, free to remove

None of these links works .. --174.67.243.57 (talk) 15:54, 21 February 2014 (UTC)

Rewrite in progress

I'm doing it user space right now. If you plan to edit the article in the nearest week or two, ping me please. East of Borschov 13:21, 3 November 2010 (UTC) done. East of Borschov 17:36, 5 November 2010 (UTC)

Generic trademark, etc.

Weber's book seems sufficient to claim that Vactrol is used generically today. He writes: "The light dependent resistor, also known as LDR or vactrol, is a device... " Tijfo098 (talk) 18:57, 5 November 2010 (UTC)

Expert Needed

What does

Both transformers and opto-couplers are effective in breaking ground loops caused by high or noisy return currents in ground wires, and common in industrial and stage equipment.

mean? I cannot fix it without knowing what the writer intended.--Anon423 (talk) 19:36, 6 November 2010 (UTC)

1. High and noisy electric currents are common in industrial equipment
2. Noisy [but not really high] currents are common in stage equipment
3. Return currents (i.e. currents returning to the power supply through the return wires) cause ground loops.
4. Transformers and opto-couplers can break ground loops, so the noise in return wires stays there and does not disrupt useful audio and video signals. East of Borschov 00:48, 7 November 2010 (UTC)

Thank you. I have reworded it to hopefully make it better.--Anon423 (talk) 02:01, 7 November 2010 (UTC)

Does

All materials used in opto-isolator packages must have matched thermal expansion properties.

refer to just silicone dome designs, or to all opto-isolators? It is unclear from the context.--Anon423 (talk) 19:49, 6 November 2010 (UTC)

• Ah, this is precisely the case of awkward paraphrasing of what was a crystal-clear sentence. The source meant that the thermal expansion coefficient of the dark goo must match t.e.c. of clear silicone (applicable only to double-molded silicone domes). Quote: "A dark outer mold compound, with a matched thermal expansion coefficient to the inner-mold compound, is then called an over under double molded design." East of Borschov 00:40, 7 November 2010 (UTC)
  • p.s. "matched" does not [necessarily] mean "equal" or even "close". East of Borschov 00:56, 7 November 2010 (UTC)

Thanks.--Anon423 (talk) 02:01, 7 November 2010 (UTC)

Copy-edit

I have copy-edited the article, but am holding off on removal of the copy edit tag for now until I can get some feedback on my work. I have also added an expert-subject tag for the confusing sections. —Preceding unsigned comment added by Anon423 (talk • contribs) 00:25, 7 November 2010 (UTC)

• Thanks. I'll check diffs one by one - at first sight there's one instance when copyedit changed the intended message to something else. Check the sentence "They feature speeds four times higher, lesser power consumption and lower cost than the fastest contemporary opto-isolators." (last section). Apart from a change of tense (it's a snapshot of 2000 market, past tense) I'm not sure that any product can "feature" low cost. "Low cost" in industry-speak means "low price to wholesale buyers", it's the seller's decision and not a property of a product. East of Borschov 00:36, 7 November 2010 (UTC)

I'm removing both cleanup tags at the top. Thank you.--Anon423 (talk) 02:04, 7 November 2010 (UTC)

Possible Merge with Solid-state relay

considering the fact that Solid State Relays use Optical isolators, having both articles separate seems redundant (contributor formally known as KB1KOI) 2012-12-03, 18:20 UTC — Preceding unsigned comment added by 216.19.115.116 (talk) 18:19, 3 December 2012 (UTC)

Article name is not compliant to international standard

The International Standard IEC60050 for the naming of electrotechnical components only accepts the names "photocoupler" and "optocoupler". Is there a reason why the article name is non standard? --91.15.67.235 (talk) 09:05, 24 August 2013 (UTC)

Requested move 30 April 2016

The following is a closed discussion of a requested move. Please do not modify it. Subsequent comments should be made in a new section on the talk page. Editors desiring to contest the closing decision should consider a move review. No further edits should be made to this section.

The result of the move request was: no consensus with no prejudice for a new discussion to be started for the "Optoisolator" alternative. (non-admin closure) Steel1943 (talk) 23:08, 25 May 2016 (UTC)

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Opto-isolator → Optocoupler – Most, if not all, manufacturers refer to these devices as Optocouplers. It is true that some also give opto-isolator as an alternative name. The primary function of the device is to provide signal coupling by optical means. The device has a valuable secondary chartacteristic of providing electrical isolation by a dielectic barrier. Constant314 (talk) 16:17, 30 April 2016 (UTC) --Relisted. George Ho (talk) 06:11, 8 May 2016 (UTC)

• Oppose, but drop the hyphen -> Optoisolator. The term opto-isolator has given was over the years to optisolator, and the two together are more common than optocoupler (or about equally common in most recent years per n-grams). The isolation function is usually the reason for using this as opposed to a simpler kind of coupling such as a wire. Dicklyon (talk) 13:59, 10 May 2016 (UTC)

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The above discussion is preserved as an archive of a requested move. Please do not modify it. Subsequent comments should be made in a new section on this talk page or in a move review. No further edits should be made to this section.

Dielectric vs insulator

Are we sure "dielectric" is the right word for the bit in the middle of an optoisolator? A dielectric is an insulator that can be polarised. This is surely not necessary in an opto, it only needs to be an insulator (and transparent!). Are dielectrics used in real-life optos, if they are, why? Is it a necessary property? Couldn't a theoretical opto be built that meets all the specifications, using a non-dielectric insulator? Depending on this, wouldn't "insulator" be a better word? It'd also be advantageous to beginners in electronics, who might not know what a dielectric is. After all, someone experienced in electronics wouldn't need to look up what an opto is!

84.67.73.190 (talk) 05:03, 19 November 2020 (UTC)

It seems to be the jargon used in describing optocouplers. At least one book I have open right now says "dielectric" and "insulator" are synonymous terms.(Electrical Conduction in Solids:An Introduction, Daniel D. Pollock, American Society for Metals, 1985 ISBN 0-87170-203-7, page 241) What insulators cannot be polarized? --Wtshymanski (talk) 06:20, 20 November 2020 (UTC)