What To Know
- Dark spots on projector images can be caused by issues ranging from a dirty lens, overheating, damaged LCD, a faulty DMD chip, an old lamp, to a burnt polarizing film, each requiring specific cleaning or replacement solutions.
- Preventing dark spots on projectors largely involves managing overheating by regularly cleaning fans, not obstructing vents, and avoiding prolonged exposure to outdoor conditions.
- Ignoring even minor dark spots can lead to more significant problems, making timely troubleshooting and maintenance critical to prolong the projector’s lifespan and avoid costly repairs.
Dark spots on a projector image can be a frustrating issue, signaling the need for immediate attention to maintain optimal functionality. This article dives straight into identifying the causes and providing efficient solutions for those encountering this common projector problem.
Dark Spots on Projector Images: Causes and Fixes
Not all dark spots on your projector are the same. Some are big, and some are small. And there are different colors too—brown, black, white, yellow, etc.
The following are the possible reasons and the possible remedies:
1. Dusty Lens or LCD
If the dark spot is small, it’s primarily due to a dirty external lens or dust on the internal LCD.
Solution: Whether the dark spots are minuscule or otherwise, give the lens and the innards a thorough clean.
There are two ways to do the cleaning. Here’s the first method:
- Turn off your projector and let it cool down completely.
- Next, unscrew the projector to open the panel.
- Start cleaning the spots using a dry, clean, lens-friendly microfiber cloth or wipe, such as this MagicFiber Microfiber Cleaning Cloths or Koala Lens Cleaning Cloth .
You may have to do a lot of unscrewing to get to the lens and its surroundings, as demonstrated in this video:
After cleaning, turn on the projector and see if the spots are still there. If they stay put, the issue may be more technical and complex than initially imagined.
If you’re unsure about revealing the device’s guts, there’s another, less intrusive way to get things done.
Some projectors provide access through a tiny door, usually hidden under the product label on the bottom of the projector.
You can clean it by opening that lid. To clean it you’ll need a clean, dry cotton swab.
Warning: The projector lamp becomes hot to the touch very quickly and the light is extremely bright. Keep that in mind when cleaning the projector while it’s still on to avoid burning yourself.
Here are the steps for cleaning the lens:
- Turn the projector upside down to access its bottom. You need not turn off the projector.
- Look for a product label. Remove the label to reveal the small access gate.
- Pry open the door or unscrew the lone screw holding the flap in place. Since the projector is powered, you’d be greeted with an extremely bright light source. Do not look at the light to not damage your eyes. Cover the light source with your hand if that helps.
- Put the cotton swab in the opening and clean the lens or the LCD screen. The swab’s silhouette will appear on the screen, helping direct the Q-Tip.
If you like the real-time cleaning feedback but are wary of the projector being too hot to the touch, turn the device off and let it cool for some time. Once the heat has dissapitated, turn on the projector and start cleaning.
Since it takes only a few minutes to clean the spots, the projector getting too warm again during the cleaning sessions shouldn’t be a concern.
Here’s a video demonstrating the steps above:
Once you’re done cleaning, put the lid and label back on. Conclude the process by wiping the lens from the outside with a dry microfiber cloth.
If the spots are white, black, or brown, it could be the device’s LED light circuit overheating or the lack of a proper cooling system.
Projector fans could get clogged due to dust accumulation, lack of lubrication, or extended projection sessions, not doing their job in the process.
Solution: The issue is dirt and dust accumulation in the fan. Clean the fan. If the fan still doesn’t work, get a replacement fan.
If the overheating issue had been unchecked for a long period, the core components could have been damaged. In such cases, you’ll have to replace them too.
3. Damaged LCD Display
When the projector gets too hot, some elements of the small LCD monitor could have been burned.
Solution: Repairing the LCD is not an option, but you can replace it. Unfortunately, changing the LCD could be expensive. Also, you’d probably require a skilled technician to do the work.
4. Broken DMD Chip
The DMD (digital micromirror device) is a silicon chip vital to any DLP projector’s functioning. The chip is comprised of multiple tiny mirrors with reflective aluminum surfaces.
Each mirror represents one pixel or spot of any image, and all the pixels together make up an image. Despite their enormous population, the multiple tiny mirrors are adept at working in sync.
But in the rare case when they don’t, dark spots could appear on the screen.
Solution: If the DMD chip is broken or malfunctioning, the only solution is to replace it. Get an expert or talk to customer support to replace the chip and confirm the DMD chip is faulty.
If your device is under warranty, the manufacturer will do the replacement for free. If not, you may have to buy the chip on your own and get a professional for the installation.
5. An Old Lamp
Although the signs of an aging lamp are usually reduced in brightness, some bulbs could exhibit dark spots on images instead to remind you of their state.
If your lamp is nearing its end of life, the dark spots could be due to the diminishing bulb. But if the projector is relatively new, the light is likely not the cause.
Solution: Change the lamp once it’s confirmed the light source is the issue.
6. Burnt Polarizing Film Glass
If the polarizing glass display filter has burn spots, it will show in the projected images.
The polarizing film on the glass filter could have burned due to overheating and subsequent spotting, once again because of a sub-par or non-functioning cooling fan.
Solution: The glass filter burns usually cannot be fixed. You’ll have to replace it with a new polarizer, like this one.
- Polarization: Linear, Size: 7.8x11.8 inches/ 20x30cm, Thickness: 0.19mm.
- Polarizing film with adhesive: Both sides have protective film, one side is adhesive. Before you use...
- Wide Application: Used for Motorcycle dashboard display, small size screen, electronic watch screen.
Last update on 2023-12-05 / Paid Link.
Replacing the polarizing film is not a simple process. So, if your projector is under warranty, send it for repair.
If the warranty period is over, you may want an expert to look at it and do the replacement.
7. Leaving the Projector Outdoors
Limited sun exposure is beneficial to your body and skin. But your projector doesn’t require any vitamin D.
If you do a lot of projector sessions outdoors under the bright sun, with or without shade, your projector will heat up a lot more than usual, causing dark spots on the projected images and, most likely, a host of other concerns.
Not to mention, your projector will become more prone to outside air and the various particles in it, making it much easier for the filter to get clogged up, causing overheating problems.
Solution: Don’t do projector sessions outdoors, especially if you live in a warm place or your projector is prone to overheating.
Sporadic outdoor projector sessions are fine but don’t make that a habit. Most importantly, ensure your projector is under shade and clean the device immediately after you take it indoors.
Preventing Dark Spots in Your Projector Images
If you want to know how to prevent the spots from appearing, unfortunately, there are not a lot of specific prevention measures you can take.
The above issues clarify one thing: overheating is at the root of it all. If you can control your projector’s temperature, you can avoid dark spots and other related concerns.
And preventing excessive heating would mean cleaning the fans regularly, not blocking the projector’s vents, not taking it outdoors, etc.
Projectors heating is normal, but overheating is not. Therefore, turn off the device if it gets too hot to touch or if the fan is too loud. And if the projector gets extremely hot within minutes, there may be another significant issue.
Dark spots on projector images may seem innocuous at first. But the dots will multiply and get bigger if you don’t get to the root and try fixing the problem.
When you leave the issue unattended, the problem exacerbates over time, necessitating a potentially arduous and expensive repair job. In some cases, the projector could be beyond repair or warrant the parts’ replacement, costing close to a new projector’s price.
Therefore, do not be indifferent. Make a checklist of the above causes and tick them off one at a time following the suggested solutions.
If the spots remain after all your hard work, you may be looking at something that your manufacturer or a projector expert can best handle.
Catherine Tramell has been covering technology as a freelance writer for over a decade. She has been writing for Pointer Clicker for over a year, further expanding her expertise as a tech columnist. Catherine likes spending time with her family and friends and her pastimes are reading books and news articles.