![]() It seems this difference in compensation cycle could explain why we're seeing more image retention, and now burn-in, on the Sony TVs than we are on the LGs. This difference means that for the duration of this test, LG TVs will run 21 small compensation cycles per week, while Sony TVs will only run 3. They both run it after four hours of total use once the TV is in standby mode, but while LG TVs run the cycle immediately after putting the TV into standby mode, Sony TVs only do so once the TV has been in standby mode for another four hours. We know from our original soft-launch period that LG and Sony TVs implement the small compensation cycle differently. In this case, though, we're mainly interested in the small compensation cycle, as it's more likely to have an impact on the short-term results of this test. The larger cycle runs after a much greater number of hours, anywhere between 500-2000 cumulative hours, depending on the brand and model. The first, smaller cycle, runs automatically after the TV is put in standby mode after four hours of cumulative use. Each manufacturer implements this slightly differently, but they almost all have two separate compensation cycles. All OLED displays, including monitors, have two built-in compensation cycles designed to reduce temporary image retention or uniformity issues. Our leading theory for this issue is that the differences in burn-in performance mainly have to do with the compensation cycles. ![]() So what else could explain the difference between LG and Sony? Compensation Cycles The two Sony WOLED TVs that still have burn-in, the Sony A80J and A90K, use WBC and WBE panels, respectively, so it doesn't appear that the panel type makes much of a difference as far as burn-in is concerned. So what does this information tell us? Both LG and Sony TVs on this list use a mixture of WBC and newer WBE panels and have different long compensation cycles. They also have major differences in software/firmware, and even models from the same company, sharing the same underlying panel, sometimes have significant differences between them, including the frequency of their compensation cycles (more on that later). They use different power supplies, motherboards, and most major components. Other than those two major components, almost everything is different. They also all use timing control boards, or T-CONs, made by LG Display, but the exact board varies from one model to another. They share the same OLED layer (that is, the part of the screen that emits light), but there appear to be other differences between the final panel stacks, up to and including the top glass, that we can't investigate at this time. We found that LG and Sony TVs have very little in common. We also went into the service menu for each one to find the exact panel used and if it was a WBC or WBE panel. We exported the spectral power distribution (SPD) charts for all OLED TVs involved in this test, and we fully disassembled the LG A1 OLED, the LG G1 OLED, and the Sony A80J OLED. We know that LG Display makes the OLED panels for both LG Electronics and Sony OLED TVs, but what about the other components? We decided to build a database of the different TVs and look into the specific panels used to look for any patterns. To understand the difference between LG and Sony, we first wanted to determine how much these TVs have in common. We found there's no difference between LG and Sony TVs in this regard-they both couldn't keep up, and the temperature increased dramatically due to the lack of ABL. Although this procedure was only run on the Sony OLEDs with image retention, we also ran the recovery video on an LG OLED to see if their temperature increased due to the fast-changing pattern. This led to a fairly significant temperature increase on all TVs, so we had to reduce the display brightness to avoid causing permanent damage. In our attempts to clear up any image retention on these TVs, we encountered an issue very early on in that the TVs were running at full brightness, and ABL wouldn't kick in with such a rapidly changing pattern. This video quickly alternates between different colored images. We decided to run a pixel refresh video to stimulate the OLED pixels and hopefully clear any image retention. The first step here was to determine if this was permanent burn-in or just severe image retention, as we encountered during the two-week soft launch of our test in October 2022. The Sony A8H, A80K, A80J, A90J, and A90K all showed severe signs of image retention. LG C2 OLED - 50% slide showing no image retention after two monthsĪfter taking our two-month photos and measurements, we were surprised to see what looked like severe image retention on some of our WOLED displays.
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