We see a lot of logos inserted into our poster templates that look like this. What is happening is that the logo looks OK when it’s small on your computer screen, but when you make it larger on your poster, it doesn’t have enough pixels to look good. We call this pixelization. Pictures can give you the same problem. All images, when digitized, are divided into small squares of colors called pixels. The goal is to make them small enough that you don’t notice them. When you don’t have enough, you get pixelization.
The way to solve this problem is to get a decent logo file. Often, the Public Relations or Graphic Design department at your institution will have one. A good high resolution (hi-rez in graphic design lingo) jpg file will work great. Later versions of PowerPoint will usually import an eps file, which is the other file format that is common.
We have a large library of hi-rez logos that we have accumulated over the years, and are happy to send you one. Just give us a call! Once you have a good file, you can import it into your poster template using insert>picture> from file.