  We present a new system of narrow band filters in the near infrared that can
be used to classify stars and brown dwarfs. This set of four filters, spanning
the H band, can be used to identify molecular features unique to brown dwarfs,
such as H2O and CH4. The four filters are centered at 1.495 um (H2O), 1.595 um
(continuum), 1.66 um (CH4), and 1.75 um (H2O). Using two H2O filters allows us
to solve for individual objects' reddenings. This can be accomplished by
constructing a color-color-color cube and rotating it until the reddening
vector disappears. We created a model of predicted color-color-color values for
different spectral types by integrating filter bandpass data with spectra of
known stars and brown dwarfs. We validated this model by making photometric
measurements of seven known L and T dwarfs, ranging from L1 - T7.5. The
photometric measurements agree with the model to within +/-0.1 mag, allowing us
to create spectral indices for different spectral types. We can classify A
through early M stars to within +/-2 spectral types, late-type M and L dwarfs
to within +/-0.3 spectral types and T dwarfs to within +/-0.1 spectral types
1-sigma. Thus, we can distinguish between a T1 and a T3 dwarf. The four
physical bands can be converted into two reddening-free indices, mu1 and mu2,
and an extinction, AV, for the individual object. This technique, which is
equivalent to extremely low resolution spectroscopy, can be used to survey
large areas to provide rough spectral classifications for all the stars in the
area, ranging down to the coolest brown dwarfs. It should prove particularly
useful in young clusters where reddening can be high.
