Fix Poor Scan Quality and Streaks on Your Printer

Blurry, dark, or streaked scans mean your scanner cannot capture a clean picture. Vertical lines usually come from debris on the glass, while low DPI settings make text pixelated. You might assume the machine is broken, but the hardware is usually fine.

Other issues have simple causes. Incorrect brightness makes documents look washed out, and JPEG compression leaves artifacts. Curled paper creates shadows and blurry spots because the page sits too far from the glass. If you use the automatic document feeder, remember that the ADF glass strips require separate cleaning from the flatbed glass.

Real hardware failure does happen. CIS element failure causes unremovable lines, and scratched glass produces permanent white lines on every scan. Those physical defects are less common than simple dirt or outdated drivers causing software communication errors.

• Dust or debris on the flatbed scanner glass
• Smudges or correction fluid on the automatic document feeder glass strip
• Scan resolution set too low
• Document fed crookedly through the automatic feeder
• Incorrect brightness and contrast settings
• Low quality compressed file format selected
• Internal scanner sensor hardware failure

1. 1Determine if the defect occurs only when using the automatic document feeder or the flatbed glass as well
2. 2Make a physical copy to see if the issue replicates on printed output

1. 1

   Clean the Flatbed Glass

   Wipe the glass surface using a lint-free cloth dampened with isopropyl alcohol or glass cleaner. Dry with a dry cloth.

   Do not spray liquid directly onto the glass.

2. 2

   Clean the ADF Scanner Strip

   Locate the small secondary glass strip used by the automatic document feeder and clean it thoroughly to remove streaks.

   Do not use abrasive cleaners.

3. 3

   Increase Scan Resolution

   Open your scanning software and increase the DPI setting from 200 to 300 or 600 for sharper text.

4. 4

   Change File Format

   Switch the output format from a heavily compressed JPEG to PDF or PNG to reduce compression artifacts.

5. 5

   Adjust Brightness and Contrast

   Use the scan software settings to lower brightness or increase contrast if text appears washed out.

6. 6

   Flatten Original Documents

   Smooth out wrinkles or curls in the paper before placing it on the glass or feeding it through the ADF.

7. 7

   Run Scanner Calibration

   Access the printer maintenance menu from the control panel or computer software and select scanner calibration.

8. 8

   Update Scanner Drivers

   Download and install the latest TWAIN or WIA scanner drivers from the manufacturer website.