diff --git a/config/initializers/hexapdf.rb b/config/initializers/hexapdf.rb
index a734508a..a51bbaef 100644
--- a/config/initializers/hexapdf.rb
+++ b/config/initializers/hexapdf.rb
@@ -1,8 +1,8 @@
 # frozen_string_literal: true
 
-# fix NoMethodError: undefined method `field_value' for #<HexaPDF::Type::AcroForm::Field
 module HexaPDF
   module Type
+    # fix NoMethodError: undefined method `field_value' for #<HexaPDF::Type::AcroForm::Field
     module AcroForm
       class Field
         def field_value
@@ -10,5 +10,34 @@ module HexaPDF
         end
       end
     end
+
+    # comparison of Integer with HexaPDF::PDFArray failed
+    class CIDFont < Font
+      private
+
+      def widths
+        cache(:widths) do
+          result = {}
+          index = 0
+          array = self[:W] || []
+
+          while index < array.size
+            entry = array[index]
+            value = array[index + 1]
+
+            if value.is_a?(Array) || value.is_a?(HexaPDF::PDFArray)
+              value.each_with_index { |width, i| result[entry + i] = width }
+              index += 2
+            else
+              width = array[index + 2]
+              entry.upto(value) { |cid| result[cid] = width }
+              index += 3
+            end
+          end
+
+          result
+        end
+      end
+    end
   end
 end