class thinfilmstack{


	complex<double> theta_incident_from_previous_film;
	complex<double> n_previous_film;
	complex<double> Mperp[3][3],Mpara[3][3];  //TN6
	complex<double> current_theta;	
	double lambda;

	public:

	complex<double> p,q;
	complex<double>p1,q1;   
	complex<double>pl,ql;  

	thinfilmstack::thinfilmstack(complex<double>n1,complex<double>n3, complex <double> theta_in,
		double input_lambda, double data_array[],int numfilms);
	void AddLayer(double thickness, complex<double> n);
	void MatMult( complex<double>A[][3], complex<double>B[][3], complex<double>C[][3]);

	complex<double> r_perp(void){
		return (  ((Mperp[1][1]+Mperp[1][2]*pl)*p1-(Mperp[2][1]+Mperp[2][2]*pl)) / ((Mperp[1][1]+Mperp[1][2]*pl)*p1+(Mperp[2][1]+Mperp[2][2]*pl)) ); };		
	complex<double> r_para(void){
		return (  ((Mpara[1][1]+Mpara[1][2]*ql)*q1-(Mpara[2][1]+Mpara[2][2]*ql)) / ((Mpara[1][1]+Mpara[1][2]*ql)*q1+(Mpara[2][1]+Mpara[2][2]*ql)) ); };		
	complex<double> t_perp(void){

		return (                                                           2*p1  / ((Mperp[1][1]+Mperp[1][2]*pl)*p1+(Mperp[2][1]+Mperp[2][2]*pl)) ); };	
	complex<double> t_para(void){

		return (                                                           2*q1  / ((Mpara[1][1]+Mpara[1][2]*ql)*q1+(Mpara[2][1]+Mpara[2][2]*ql)) ); };	
};


class reflection{
	//Ref: M. Born and E. Wolf, "Principles of Optics", sixth edition, 1993, Chapter 13.
	// all notation per the reference

	complex<double>n_hat;   //n"hat" per Born and Wolf notation: complex index of refraction of transmitted medium
	complex<double>theta_i; //incident angle. 

	public:		
	reflection(complex<double> , complex<double>);//n_hat and theta_i

	complex<double> theta_t;	//transmitted angle
	complex<double> calc_theta_t(void){return arcsin(sin(theta_i)/n_hat);};


	complex<double> r_para(void){ //Technical Note TN3  see below
		return (sin(theta_i-theta_t)/cos(theta_i-theta_t))/(sin(theta_i+theta_t)/cos(theta_i+theta_t));};

	complex<double> r_perp(void){
		return (sin(theta_i-theta_t)/sin(theta_i+theta_t));};	
};