The Welcome Lounge: introduce yourself 👋

Hi Richard, welcome to Which? Conversation.

I think we do not have a specific topic for screen burn on Sony TV’s, but we do have a more general Conversation for product liability and consumer rights, see:-https://conversation.which.co.uk/shopping/consumer-rights-complaints-faulty-problems/

I’m very happy with my 10 year old 32″ Sony Bravia HD TV, so it is a shame to hear that you are having bother with a much newer model.

As a first step, I think the consumer rights act 2015 places the burden of product liability on retailers not manufacturers, but we do know that some retailers tend to misdirect customers with problems towards manufacturers.

The consumer rights act also requires good to be reasonably durably, i.e. an expensive quality TV should be defect free for around 10 years as a minimum.

Thankyou for your guidance. I had in fact researched your site for Consumer Rights info and will use it to tackle Curry’s/ PC World tomorrow. I’ll keep the Community posted.

Hi Richard and welcome to Which? Conversation.

Screen burn was very well known in the days of CRT screens, especially when static images are displayed for a prolonged period at high brightness. It can also occur on OLED screens. Here is a relevant article from Which? https://www.which.co.uk/news/2018/09/is-screen-burn-on-oled-tvs-worth-worrying-about/?source_code=911CQJ&gclid=Cj0KCQjwxNT8BRD9ARIsAJ8S5xaP52PkthwVAXnD6KssIeq1kgCa4LwHfb156UjUKwsV3kmUqdgb4n8aAgm9EALw_wcB&gclsrc=aw.ds

There are numerous Conversations that mention consumer rights and here is one of the most active ones: https://conversation.which.co.uk/shopping/consumer-rights-complaints-faulty-problems/ I hope you will join us as a regular contributor.

DetekP, just on a detail. While I agree that tvs should last at least 10 years (as should many products) the Consumer Rights Act only gives legal protection for 6 (apart from the unlucky Scots who get 5).

Many products do last well, and these should be used to demonstrate that it is not difficult to achieve if you design a product competently, specify decent components and build it well. We should be campaigning against manufacturers who do things badly. We could use the “durability” clause (or lack of) given to us in the CRA much more than we do to put financial pressure on retailers to sell decent products and avoid the tat. Which? should (and I think could) devote resources to help here; a more useful cause than some others they pursue.

Malcolm, thanks for that correction. I’ve known even “ordinary” TV’s like LG and Samsung to last for 6 years or more.

Under the Consumer Rights Act, the customer has six or five years during which they can make a claim against a retailer. For the first six months, a fault is presumed to be present at the time of manufacture, after which it is the responsibility of the consumer to prove otherwise if requested (e.g. by providing an expert’s report) or to provide evidence that goods have not lasted as long as might reasonably be expected. After six months, any refund can take account. of the amount of time between purchase and when the fault was reported.

A manufacturer’s guarantee can provide additional rights and is usually easier to to use than the CRA. It may contain exclusions but does not override the statutory rights provided by the CRA. Once again, a claim should be made against the retailer.

Neither the CRA or manufacturer’s guarantee will provide protection against abuse/misuse or normal wear & tear.

You’re getting screen burn?

Interesting. I thought that went out with CRT

Is it new and unused? There shouldn’t be screen ghosting if it was from stock, ex shop display is a different matter as they’re usually thrashed and over-driven to an inch of their lives.

I’ve a Sony Bravia too.

Upon first getting it I hired an ISF certified screen calibrator to get it calibrated.
First thing the Calibrator he told me about was “out of box” (OOB) settings,
they’re almost always incorrect for home/cinema use and designed to wow in super bright shop floors.
Second thing he cautioned me about was the backlight, which can prematurely age a screen if too high, so he halved that.

Do you have static images on display for long periods? Or parts of the broadcast that persistently display the same image?
BBC News24 does this with their onscreen banners/marquees, e.g. My screen is often connected to a PC, so I make use of the screen’s idle function and the PC’s screensaver.

Screen burn is still very possible on TVs since CRT.

Our 2007 plasma screen had the Sky pause button permanently engraved in the corner until the screen failed and was replaced during the 5-year warranty. We were unaware this was a problem when we first had the TV but have been much more careful with the replacement screen and it is still going strong with no obvious screen burn.

The first thing our 2018 OLED manual says straight after the index is:
Important Notice
Do not display any still part of the image for a long period.
In such cases the still part of the image remains dimly on the screen (“image retention”). This is not considered a malfunction and is not covered by the warranty.
● Typical still image parts:
• Still images shown continuously on the same area (ex. channel number, channel logo, other logos or title image, etc.)
• Still or moving pictures viewed in 4:3 or 14:9 aspect ratio, etc.
• Video games

If we need to pause anything on this TV, we put the screen into standby.

Hi Helen and welcome to Which? Conversation.

At present a manufacturer has no legal responsibility for faulty goods but they often handle recalls of products that are found to be dangerous. If the retailer, which is legally liable, is unhelpful, the manufacturer will sometimes help, presumably because they want people to carry on buying their brand. Presumably the retailers can reclaim costs from manufacturers for dealing with faulty goods.

I have generally been happy with Bosch products though the company did not even acknowledge a complaint about a reciprocating saw with no safety interlock, unlike other brands and even other models in their range.

It would be interesting to hear about your experiences with Which? Legal.

The reason the manufacturer is not legally liable to the customer is because, normally, by purchasing through a retailer your legal contract is with them. I would argue that in selling a product they also take responsibility for the choice they have made to promote it.

Given the worldwide distribution of manufacturers, some in countries beyond our jurisdiction, others in countries not subject to UK/English law, it would be very difficult to pursue a claim direct. Hence the responsibility is best with the UK supplier.

However, you will also have a warranty from the manufacturer which also gives you rtights that you can exercise separately from the retailer, although I suggest the retailer should be kept informed in case any further fault develops when the warranty has expired.

To say the manufacturer has no responsibility for faulty goods may not be the case. They may well be liable legally to the seller by virtue of their purchase contract.

Hi chrisandy – Welcome to Which? Conversation. It’s always good to have new faces. There are new topics and many older ones that are periodically revived.

Hi Misha – Some fluorescent lighting (magnetic ballast) produces a visible flicker that is noticeable to some individuals including me, but I am not aware of a problem with modern LED lamps. The articles you have provided links for are quite old and designs of LED lamps have changed.

I suggest using mains voltage LED lamps rather than ones that need a separate driver, and it is important to use a dimmer that is specifically for LED lighting. Dimmers for halogen lamps may cause flickering and cause LEDs to behave unpredictably.

There are regulations that limit the amount of radio frequency emission that electrical products can emit to avoid radio and TV interference but I am not aware of anything specifically related to flicker.

Hi wavechange,

Many thanks for your reply.

I’ve found a newer paper (from 2015), which appears to be the outcome of the deliberations mentioned in the introduction to the first paper I quoted earlier. It’s called “1789-2015 – IEEE Recommended Practices for Modulating Current in High-Brightness LEDs for Mitigating Health Risks to Viewers” and is available here:
http://bio-licht.org/02_resources/info_ieee_2015_standards-1789.pdf

And here’s an even newer paper, from 2019, called “Light Emitting Diode Lighting Flicker, its Impact on Health and the Need to Minimise it”:
https://jcdr.net/articles/PDF/12880/41491_220419_41491_CE%5bRa1%5d_F(KM)_PF1(AJ_SHU)_PFA(SL)_PN(SL).pdf

The light fittings our electrician installed are described here:
http://www.allledgroup.com/index.php?route=product/product&product_id=630
Neither the product page, nor the accompanying data sheet, mention a driver, but I’m not sufficiently technical to say for sure that there isn’t one. Can you tell?

The bulbs the electrician fitted are described here:
http://www.allledgroup.com/index.php?route=product/product&product_id=468&search=AGU501D%2F27

Our electrician told us that the new dimmers he installed are designed for LEDs. I’ll need to ask him for their make and model.

Thanks very much for these links, Misha.

Your light fittings take GU10 lamps, which are mains voltage and there is no driver to complicate matters. If the dimmer(s) are designed for LEDs (sometimes called ‘trailing edge dimmers’ and dim the lamps progressively without any sign of flickering they are not obviously creating a problem. Nevertheless, dimmers work by switching the lamp on and off at a frequency that is too high to be perceptible and it might be worth running the lamps at full brightness to see if that eliminates the nausea and headache you have mentioned. If that works you could replace the LED lamps with ones that are less bright.

LED lamps themselves produce slight flicker because they are run from AC mains, which means that the light output cycles up and down, again at a frequency too high to be visible. LED lamps consist of blue LEDs and a fluorescent phosphor that converts blue light into white light. The phosphor helps to reduce flickering.

Although LED lamps contain a rectifier to convert AC to DC there is not enough room to include a large capacitor that would be needed to remove all flickering. That is one of the problems with making lamps that are a plug-in replacement for incandescent bulbs. It might be worth swapping to LED lamps from a different manufacturer. You might get some useful advice from the major manufacturers.

I have never had any problems with LED lighting and my interest is because I suffer from a headache and nausea very quickly if I use an stroboscopic tachometer to measure the speed of rotation of motors etc. I also find faulty lighting (see Beryl’s post below) very unpleasant. I am only affected when flickering is obvious, though you and others seem to be affected by higher frequencies where it is not possible to see flickering. This is mentioned in the IEEE article.

Please let us know if you manage to find other information or find a solution to your problem.

Thanks, again, wavechange.

I’ve discovered which dimmers our electrician installed. They’re described here:
https://www.mlaccessories.co.uk/product/2460323/10200w-5150w-led-trailing-edge-led-dimmer-module
As you advised, they are trailing edge dimmers.

Tonight, I’ll try the lights at full brightness, as you suggested.

I’ve also found another two relevant articles:

1. “The scientific reason you don’t like LED bulbs — and the simple way to fix them” published in 2017 in The Conversation (https://theconversation.com/the-scientific-reason-you-dont-like-led-bulbs-and-the-simple-way-to-fix-them-81639) and in the Scientific American (https://www.scientificamerican.com/article/the-scientific-reason-you-dont-like-led-bulbs-mdash-and-the-simple-way-to-fix-them/). The words “and the simple way to fix them” seem to be false advertising as the article doesn’t appear to describe a simple solution.

2. “Flicker: A Hazard of LED Lighting” (https://energyperformancelighting.com/flicker-a-hazard-of-led-lighting/). This article (unlike the others) appears on a commercial Web site but seems (to my non-expert eyes) to make sense. It was last updated in 2019. I’ll quote some of it below. Apologies for the length of the quote, but it seems worth it. Note the distinction it makes between visible flicker and invisible flicker.

LEDs and Flicker

Flicker is exactly what it sounds like – light output from a given source changing repetitively over time – similar to flicking the light switch on and off except the light output is fluctuating on its own and at a much quicker pace. There are two types of flickering with lights: visible flicker and invisible flicker.

Visible flicker (considered anything below a frequency of 100Hz) is observable by the human eye and is typically undesirable except in special applications such as stroboscopic lighting. Invisible flicker is flickering that is present but not perceived by the naked eye. If left uncontrolled, lighting flicker can cause an abundance of biological and health issues that can ruin an otherwise well-designed space. Neurological problems (including epileptic seizures), dizziness, headaches, fatigue, increased autistic behavior (especially in children), eyestrain, impaired thought, and migraines are some potential flicker-induced impairments.

What Causes Flicker?

For LED lighting to perform optimality, it should be run on direct current (DC), since there is a constant stream of current through the circuit. But because electricity in the U.S. is delivered through alternating current (AC), voltage delivered to a source fluctuates between on and off as it bounces off the positive and negative poles of the sine wave (unless the current is maintained in some way). A source without quality electronic circuitry – such as a ballast, driver, or capacitor — will flicker.

Another cause for flicker is with dimming and control circuitry that uses a method called PWM (pulse width modulation). PWM cycles the LED from the maximum current to zero current, essentially switching the current on and off very fast, and repeats this process at a fixed rate. Dimming is controlled by the driver, so choosing the proper driver is crucial to getting the desired lighting effect. Drivers that use PWM at a low enough frequency have a high potential to introduce undesirable flicker.

How to Reduce LED Flicker

The key to reducing flicker lies in a well-designed driver. The right driver can eliminate the problem of flicker by providing the LED with a constant, non-oscillating current. The issue here is that manufacturers must weigh several factors—such as size, efficiency, cost, and reliability—when deciding which driver to include in their products.

Capacitors are typically used in LED drivers to smooth and reduce the ripple that comes from the power supply. Selecting a quality capacitor for an LED lighting system can help to avoid flicker, eliminate excessive heat, and ensure the longevity of the LED lights. Even lamps with capacitors may flicker; it is a matter of the quality of the lamps and their components. Lower cost lights/lamps have lower quality capacitors.

It is also important to verify that the LED lighting product is compatible with the dimmers or other control circuits used in the lighting system. A faulty photosensor or timer can cause flicker issues. Moreover, random flickering may be an indication of another problem in the lighting system, such as loose wiring and interconnections. The quality of the electrical supply can also result in problems with power fluctuations.

Hi again Misha – I agree with your comment about the Scientific American article. SA is usually a very good source of information.

The second article is even less helpful to the layperson. For example it refers to PWM dimming, but as far as I know, domestic dimmers use phase control rather than PWM. (PWM is ideal for controlling high power loads such as heaters and specialist lighting.) It’s true that decent capacitors can reduce (invisible) flickering but there is not enough room in the cap of a lamp (especially the GU10 type) for a big enough capacitor to do the job. It is right that it would be best to run LEDs on DC rather than AC, but our mains supply is AC.

You have established that warm white (2700K) lamps are best for you. That might be because the colour temperature is low or simply because high colour temperature lamps that produce bluish light tend to be brighter than the rather yellow warm white lamps.

It might be worth visiting neighbours or friends who have LED lighting and find out whether you are affected. If not you could switch to using the same LED lamps.

Hi wavechange.

I’ve now tried setting the dimmers to maximum brightness and that does, indeed, greatly reduce the problem. Thanks for the suggestion.

We do, though, want to be able to dim the lights, eg when eating supper or relaxing around the table afterwards. This will be much more relevant later in the year, when it gets dark earlier.

I may need to ask the electrician to tweak the potentiometer built into each dimmer. The dimmer’s instruction manual* states:

If small levels of flicker can be seen in the dimming curve at the lowest point, then this can be eliminated by following the steps below

Adjusting the minimum dimming level
• Isolate the power and rotate the dimmer to its minimum position
• With the aid of a small slotted screwdriver, rotate the potentiometer
• Switch on the mains power and check for correct operation
• If flicker is still in the dimming curve please repeat the above steps

* For the dimmer’s product page, see the link in my post of 22 June, below.

Hi again wavechange.

We don’t know of any neighbours or friends who’ve taken the step of replacing all of the lighting in some room with LEDs, connected to a dimmer. 🙁

Hi Em,

Thanks for your input. I’ll look at the Philips (Signify) EyeComfort range you mentioned and will also follow up the other suggestions you made.

I have a pair of Philips Hue LED bulbs (with integral dimmers), which I’m very pleased with.

Another problem has arisen (I don’t think I should say “has come to light”) with our new LED lights. We have two banks of 8 downlights (so 16 lights in all) in our kitchen/dining room/playroom. Each bank is controlled by a dimmer. After being on for an hour or so, all the lights in a given bank go off, stay off for around 5 or 10 seconds, and then come back on. This off/on cycle then continues, with gaps of 5 minutes or so. The two banks go off and then on at their own rhythm. We’ve noticed that the area of the switch plate behind which the dimmers are located gets very hot.

This is a mystery to us as:

• The LED bulbs are described as taking 5.5W.
• We have 8 of them per dimmer, making 44W per dimmer.
• The dimmers are rated at 5-150W when used with LEDs.

Any suggestions?

Many thanks.

Hello Misha, you could swap that module to a different brand of dimmer, say MK, and see if that changes the flicker and the extinguishing.

Hi malcolm r,

The problem is that the more I look into this stuff, the more I discover that achieving a successful LED-dimmer partnership is a black art rather than a science. This makes me reluctant to try to solve the problems by throwing money at them, as I have no basis for supposing that one product combination will work better than another. I wish there was some organisation that would test these products and publish the evaluations.

I’ve found two Web pages with conversations about the problems, among people who seem to know what they’re talking about. They include horror stories, like dimmers in adjacent rooms interacting to cause problems.

I don’t want my post to get stuck in the 24-hour holding tank while the hyperlinks are checked, so I’ll try leaving out the protocol section of the hyperlinks. The two pages are:

http://www.electriciansforums.net/threads/led-flashing.191676/
forum.buildhub.org.uk/topic/18736-dimmable-led/

I was suggesting a known (hopefully reputable) supplier of dimmer modules might be worth trying, rather than an unknown (to me) make. Just substituting one may test whether it makes a difference.

“I suggest using mains voltage LED lamps rather than ones that need a separate driver, and it is important to use a dimmer that is specifically for LED lighting. Dimmers for halogen lamps may cause flickering and cause LEDs to behave unpredictably.”

Apologies being late to the party – only recently rejoined Convo after some absence. I can empathise with this problem having had bad headaches as a result of flickering fluorescent tunes in yesteryear.

If I were in Misha’s shoes and getting ill as a result of this, the first thing I’d do is “un-replace” the LED bulbs with the removed halogen ones (and “unreplace” the dimmer too as a sticking plaster solution.

I’d then seek out low voltage DC LED fittings and a a DC driver for LED lights, and finally add a DC to DC dimmer such as the one RS sells – https://uk.rs-online.com/web/p/led-lighting-controllers/7693189/ and, having jerry rigged one or two on my desk to confirm success, replace all the existing fittings with the new solution.

An alternative if this sounds too complicated, contact LED manufacturers and find the ones that use long persistence phosphors – you need one where the phosphor luminescence half life is >100ms. Provided the phosphor glow continues for substantially longer than the mains cycle, flicker should be all-but absent no matter what the driver system.

I had a similar problem with LED lightbulbs and had to change back to halogen.
Also, there is a street light at the front of my house that started to nonstop flicker that triggered a migraine with nausea. I had to phone the council to come and fix it.

There is a condition that can cause a reaction in susceptible people; a type of photophobia, which is a sensitivity to light. It’s interesting to note something can trigger a migraine where you see flashing lights at the onset or just before, can feel nauseous but without a headache. It’s known as a silent migraine.

Thanks for your comment, Beryl.

We haven’t (yet!) changed back to halogen lights in our kitchen and bathrooms but have put on hold changing the lights in our study/office from halogen to LED, pending the outcome of our investigations into the cause of the problem. We did find that swapping the LED bulbs from cool white ones (4000K) to warm white ones (2700K) helped a lot. Do you know the colour temperature of the LED bulbs you tried?

I came across the Wikipedia article on photophobia (https://en.wikipedia.org/wiki/Photophobia) during my research but the problems it describes are mostly much more severe than the ones I’m experiencing.

Since my childhood, I have (occasionally) suffered from flashing lights at the edge of my vision, which are followed by difficulty focusing my eyes and needing to minimise eye stimulation in order to avoid a migraine. I wonder whether people who suffer from this kind of symptom are more sensitive to flickering lights. I’ve just looked up “silent migraine” and found the articles interesting.

I’ve also always been made ill by going on fairground rides but have never been sure whether this is due to visual problems (ie the scenery flashing by very fast) or balance problems (ie my body not coping well with rapid changes of position). If it’s the former, then that might be related to my current problem with flickering lights.

Another question, @beryl,

You wrote that you abandoned LED bulbs and changed back to halogen ones.

Were you using a dimmer with the LED bulbs?

It seems that it is sometimes the dimmers that cause the problem.

@beryl and anyone else who might click on the link in my comment above …
I accidentally linked to a section (called “Other causes”) within the Wikipedia article on photophobia, rather than to the entire article. So if you do click on that link, please scroll to the top of the article before you start reading.

Beryl – The severe flickering and lack of proper dimming you have described are what happens if you do not have a dimmer suitable for LED lamps or you try to dim LEDs that are ‘non-dimmable’.

With a wall-mounted dimmer it is usually easy to swap to a dimmer suitable for LED lamps. Dimmers designed for LED lamps will work on halogen lamps too if you want to compare both types of lamps.

Thanks Wavechange. I would need a dual switch as there are 2 lights, totalling 6 light bulbs. I would have to hire an electrician as tampering with electricity is not something I would feel comfortable with. I will probably wait now until all the existing bulbs I have stored are used and are no longer available.

We would not want to lose you, Beryl. If you have an electrician in to do another job it should be a simple task and with luck you might never need to change an LED bulb.

Thanks Wavechznge. Having absorbed my fair share of shocks during my longevity, I now tend to avoid all contact with undercurrents. I may no longer be able to change any more lightbulbs, or the world for that matter, but I can still change myself 🙂

Welcome along Liisi. Terms and conditions of distant selling – and that is what this is – cannot overtrump the act to which you refer. If it were me having reached this impasse I’d send (by email) a letter before action demanding a full refund explaining where the barrow can be collected from with a time limit of 14 days – and on the 15th day launch a claim to the courts via MCOL.

I must add this is my opinion only – I am not a lawyer, but I think it’s time to start playing hard ball given their responses.