diff --git a/pyqtgraph/opengl/GLViewWidget.py b/pyqtgraph/opengl/GLViewWidget.py
index f931fd72..f65edec6 100644
--- a/pyqtgraph/opengl/GLViewWidget.py
+++ b/pyqtgraph/opengl/GLViewWidget.py
@@ -72,11 +72,11 @@ class GLViewWidget(QtWidgets.QOpenGLWidget):
         self._updateScreen(window.screen())
         
     def deviceWidth(self):
-        dpr = self.devicePixelRatio()
+        dpr = self.devicePixelRatioF()
         return int(self.width() * dpr)
 
     def deviceHeight(self):
-        dpr = self.devicePixelRatio()
+        dpr = self.devicePixelRatioF()
         return int(self.height() * dpr)
 
     def reset(self):
@@ -149,9 +149,6 @@ class GLViewWidget(QtWidgets.QOpenGLWidget):
         else:
             return vp
         
-    def devicePixelRatio(self):
-        return self.devicePixelRatioF()
-        
     def setProjection(self, region=None):
         m = self.projectionMatrix(region)
         glMatrixMode(GL_PROJECTION)