You could use PDF To Image Converter v2.1. PDF To Image Converter v2.1 is an expert of converting pdf to image. You could get more knowledge about it here: http://www.verypdf.com/pdf2tif/index.htm#dl. Here is the method to convert pdf to clearer png in PDF To Image Converter v2.1.
1. Launch PDF To Image Converter v2.1 in your pc.
2. Add pdf into batch process table: click “Add” button>a dialog box is popped out>double-click the pdf you want to convert, which is shown as a route in batch process table.
3. Click the open button of toolbar in preview panel>a dialog box is popup>double-click that pdf, then your pdf file could be displayed as a page in preview panel. To check on it in detail, you could use the tool buttons of toolbar in the preview panel, such as enlarge and lessen buttons, which are used for checking pdf carefully.
4. Search a file type as your objective file format: click the edit-box of “File type”>a dragging list is popup>click PNG, which is your targeting image format.
5. Choose a folder as your objective folder to store your clearer png: click “Browse” button>another dialog box is popup>select a folder>click “ok” button, which is shown as a route in the edit-box of “Destination folder”.
6. To get a clear png, you could increase DPI in option panel. DPI stands for dots per inch, which represent resolution of raster images. The greater DPI is, the larger resolution of raster image is, the bigger dimension and size are, along with the improvement of clearness of raster image. So here click the edit-box of DPI>input 189 into each of edit-box of DPI, also you could input another larger number, here we just need 189 as an example.
7. Click “Convert” button at the bottom of the panel of this converter, wait for a few seconds and close this converter by clicking “Exit” button.