begin
  ArrayGambar[1]:= Image1;
  ArrayGambar[2]:= Image2;
  ArrayGambar[3]:= Image3;
  ArrayGambar[4]:= Image4;
  ..
  ..
  ..
  ArrayGambar[20]:= Image20;
end;

var
  i,j: integer;
begin
  j:=0;
  for i:=0 to ComponentCount-1 do
    if Components[i] is TImage then
    begin
      inc(j);
      ArrayGambar[j]:=(Components[i] as TImage);
    end;
end;

function TForm1.CariKomponen(nama: string): TImage;
var i: Integer;
begin
for i:= 0 to ComponentCount-1 do
begin
  if (Components[i].Name = nama) and (Components[i] is TImage) then
    begin
      result:= (Components[i] as TImage);
      exit;
    end;
end;
end;
procedure TForm1.FormCreate(Sender: TObject);
var i: Byte;
begin
for i:= 1 to 20 do
  begin
    ArrayGambar[i]:= CariKomponen('Image' + IntToStr(i));
  end;
end;

uses
  StrUtils;
var
  ArrayGambar: array  of TImage;
procedure TForm1.FormCreate(Sender: TObject);
var
  i: integer;
begin
  for i:=0 to ComponentCount-1 do
    if Components[i] is TImage then
      ArrayGambar[StrToInt(AnsiReplaceStr((Components[i] as TImage).Name,'Image',''))]:=(Components[i] as TImage);
end;

FindComponent();