freedom the mounting arrangements of the present invention where the number of free parameters matches the number of constraints is known as kinematic mounting 34 kinematic 34 from the greek 34 kinema 34 meaning motion refers to the fact that an element which is kinematically mounted can be removed and replaced with the second alignment being identical to the first since the number of constraints imposed by the alignment members matches the number of degrees of freedom of the element note that in fig1 the mounting is not kinematic if the balls are moved since the alignment depends on the position of the balls in the grooves if the groove patterns in the top and bottom plate are not identical if however the balls remain in place on the bottom v grooves or if the balls are fixed to the top substrate as shown in fig3 then the mounting is kinematic mounting the substrates as shown in fig1 allows for the positioning of balls to avoid defects which may be present in the grooves the alignment in fig1 will be very insensitive to the ball position if the v grooves are nearly identical note that in the arrangement in fig1 there are grooves 104 corresponding with one coordinate direction and a groove 101 corresponding to another orthonormal direction the height of each ball from the surface of the lower substrate is fixed by the depth and angle of the v grooves 101 and 104 likewise the height of the top substrate at the position of the three balls is determined by the registration of the balls.