PL/SQL: Check to see if the date is in the format of 'MM/DD/YYYY'

CREATE or REPLACE FUNCTION validate_date_format(p_input_date VARCHAR2)
RETURN BOLEAN IS

l_result_date DATE;

BEGIN

l_result_date := TO_DATE(p_input_date, 'MM/DD/YYYY');

IF LENGTH(SUBSTR(p_input_date, INSTR(p_input_date, '/', 1, 2) + 1)) = 4
THEN

RETURN TRUE;

ELSE

RETURN FALSE;

END IF;

EXCEPTION
WHEN OTHERS then
RETURN FALSE;

END;