The present invention relates to a spectroflourometer, the main embodiment of which lies in it's capability to perform the function of two instrument's in one.The spectrofluorometer of the present invention can be used as a spectrophotometer through a simple mode selection. BACKGROUND OF THE INVENTION Spectroscopy has been defined the study of the absorption and I emission of light and other radiation, as related to the wavelength of the radiation. The spectroscopic methods are helpful in almost all technical fields, especially for identifying constituents and processes in any source that emits light. With spectroscopic methods one can achieve various aims which might vary from identifying an element in a mixture to determine the structure of an unknown molecule. Besides these, the spectroscopic techniques have also found place in unraveling the scientific principles behind the structure of atom and various properties exhibited by atoms of different elements. The Florescence forms an essential aspect of spectroscopy, where the main principle behind the fluorescence is that when the light energy is incident on a substance the molecules of the substance in ground state absorb light and transit into excited state. The molecules loose portion of the absorbed energy as vibrational energy and transit to a lower vibrational level with no radiatior emitted and return to the ground state emitting some optica] energy known as Fluorescence. Since portion of the light absorbed is lost in vibrational relaxation, the fluorescence emitted by the substance has longer wavelengths than the incident light 'energy. The intensity of the fluorescence emitted is proportional to the optical energy absorbed and thus to the concentration of the substance. The spectroflourometers have been used to measure the fluorescence spectra and help interpret the results. In a spectrofluorometer, the desired wavelength of exciting light is selected by a monochromator or filter (called primary monochromator or filter) between the light source and the sample. The wavelength of light to be measured is selected by a second optical component (called secondary monochromator or filter) between the sample and a photodetector. The output of the photodetector, a current which is proportional to the intensity of the fluorescent light, is amplified to give a reading on a meter. In operation, a standard sample is placed in the instrument and the sensitivity adjusted to a desired reading. Unknown samples and a blanks are then read. The net readings (blank reading subtracted) of the standard and the samples are in the same proportion as their concentration, permitting the calculation of sample concentration by simple ratios. SUMMARY OF THE INVENTION The present invention relates to a spectroflourometer where the novelty resides not only in the fact that the spectroflourometer is more efficient, but can also act as a spectrophotometer by a mere selection of panels. The special features of the present spectroflourometer are that the invented spectroflourometer's optical geometry is configured in such a way that it performs two instrument's function in one. It can be used as a spectrofluormeter and also as a spectrophotometer through a simple mode selection. Accordingly the present invention relates to a spectroflourometer comprises a light source, focusing means to collect light from the said light source onto the entrance slit of the excitation monochromator having a holographic gratings; means for rotating the said gratings, slit mechanism connected to the said monochromator to set the slit width for a selected band width of the monochromatic radiation coming out of the said exit slit of the said monochromator, a stepper motor driven cell holder mechanism accommodating a plurality of cells employed to place one of the said sample cells in the optical path where it is being iraradiated with the selected monochromatic radiation through a excitation system, emission optical system to collect the fluorescence radiation emitted by the said sample and focusing on to the said entrance slit of emission monochromator, a fluorescence detector producing a photocurrent proportional to the fluorescence radiations emitted by the said sample on operational amplifier to convert the photocurrent produced by the said fluorescence detector into a voltage signal, an absorption detector placed in the primary radiation path of the said sample to collect the transmitted light from the said sample, ar interface circuit detector connected to the said absorptior f^c.he^r