Talk:Photoresistor

message: Hi, would anyone who knows this subject add a picture of its symbol in a circuit scheme?
Added picture of symbol alone, thought this was sufficient. Only a paint drawing done by myself, if anyone feels they can do better, be my guest. This is a symbol used in the UK as mentioned in the article, I have no idea about other countries, maybe someone who does can add further images. Wheatleya 22:44, 22 February 2006 (UTC)
thread_title:  symbol in circuit 

message: Can I please add that Light Dependent Resistors are not photocells. They do not create an electromotive force (e.m.f.), and as such are not cells. A photocell is used as part of a circuit that makes use of the photoelectric effect to provide a current around a circuit that is proportional to the intensity of light. However these are different from a LDR, which simply varies the resistance in a circuit based on surrounding light. To repeat, LDRs are NOT photocells.  —Preceding unsigned comment added by 92.12.43.166 (talk) 21:56, 26 February 2008 (UTC)
replies: text: Neither were the devices known as 'photocells' (the vacuum device with a photo emissive cathode).  They too did not create an e.m.f. but required an applied voltage to make use of them.  You are, of course, getting confused with 'photovoltaic cells' which do create an e.m.f. and hence a current (and thus power) in an external circuit. 86.166.66.41 (talk) 12:11, 4 February 2011 (UTC)
thread_title:  NOT PHOTOCELLS 

message: I've just noticed that Frozenport changed the circuit symbol of a LDR to :Image:15580.gif.  I have never seen this symbol in use, at least in the UK, and so I am going to change it back to my original.  However, if is aware that the other symbol is used in other parts of the world, they are welcome to reinsert it.  A quick Google of "ldr symbol" suggests that rectangular form is certainly more abundant.
: Following the Google link you gave, it seems that a majority of the symbols are not as you claim rectangular - in fact a majority of the rectangle shaped images come from this article! I will leave the choice of what image to use to someone else, but I have yet to find a single other place where the rectangle shape is used. --Frozenport 00:17, 9 April 2007 (UTC)
replies: text:  Although maybe we should compromise at this  --Frozenport 00:19, 9 April 2007 (UTC)
thread_title:  Circuit symbol 

message: hi, what is the average resistance of an LDR? say it is in a series circuit with a variable resistor, and a cell of voltage 12V.light wavelengths of 380nm (lowest) and 750nm (highest). if anyone can help asap that would be great!! 14 April 2007 —The preceding unsigned comment was added by 86.140.146.247 (talk) 10:56, 14 April 2007 (UTC)
replies: text: Different LDRs will vary in characteristics, but a popular device is the ORP12 (aka LDR03).  The spec sheet states that it varies from >10 Megohm in the dark to 75 to 300 ohm when illuminated at 1000 lux (with a colour temperature of 2700 K).  The cell has a max voltage rating of 110 volts and a max power dissipation of 200 mW.  In real terms this means that such a cell could easily operate a medium sized relay without any additional components (other than a power supply that is!) 86.166.66.41 (talk) 12:18, 4 February 2011 (UTC)
thread_title:  LDR voltage 

message: The description here seems almost identical to a Diode and/or a photo-voltaic (solar cell). Maybe someone who understands all three of these devices could point out what they have in common and what makes them different?
::::Tiki God 11:28, 7 September 2007 (UTC)
thread_title:  Similar Devices 

message: This should not be referred to as a "photoresistor," as far as most of the physics community is concerned.  Wikipedia is the only site Google turns up after a definition-search  for that word. The proper term is photoconductor—I think the page should be moved for encyclopedic purposes. Listing the synonym isn't enough. —DMCer™ 17:10, 27 February 2008 (UTC)
replies: text: A CdS cell is known as both a Photoresistor and a Photoconductor. Take your pick. :-) Although as far as the industry is concerned the correct name is photoresistor. For example, the big companies such as DigiKey.com, Mouser.com, and even RadioShack.com will return no search results for photoconductor, but they return search results for photoresistor. --PaulLowrance (talk) 16:03, 11 June 2008 (UTC)
thread_title:  Name 

message: Is this sometimes informally called a 'roach'? I get the impression from this video and one of the comments. --Cancun771 (talk) 20:12, 6 August 2017 (UTC)
thread_title:  Roach? 

message: The so-called "lede" section contains a 2nd paragraph that belongs in the body of the article.  
:
Observe that the second para begins with: "A photoelectric device can be either intrinsic or extrinsic..."  This is too much detail for a lede section.  This type of information should be moved down into the body of the article... somewhere.  Perhaps under a new section called something like "Types of Photoresistors", or "Design Characteristics".  Whatever.  In it's current form, the lede is WAY too complex and detailed - and serves no purpose except to scare away readers who just want to get a quick overview. 73.6.96.168 (talk) 03:55, 10 April 2021 (UTC)
thread_title:  Lede Too Complex - Too Detailed