Combine egg yolks, 1/2 cup sugar, and lemon juice in a saucepan. Cook until mixture coats a spoon. Stir in gelatin, and then mix in crushed raspberries. Chill until partially set.
Beat egg whites until stiff with 1/4 cup sugar and salt. Fold whipped cream and egg whites into raspberry mixture.
Pour filling into chilled pie crust, and chill 3 to 4 hours.