The rubber finish can make the body of green laser pointer warm

It will make the customer hold green laser pointer more conveniently and comfortable.
Independently of each oscillation mode will interact with the reverse atomic gain is basically unrelated, and derive the gain amplification and the formation of the respective steady-state oscillation, activation of the local gain saturation of the medium to medium small-signal gain curve showing multiple burn holes, each hole burning burn the lossy line, almost independent of each other, multi-mode oscillation, the laser output. The depth of the hole burning, or the degree of saturation, the size depends on the gain coefficient. Longitudinal mode optical frequency from the media center frequency is nearly the population of the population inversion density, consumption, the degree of saturation, hole burning deep; far from shallow depths. In the case of the coexistence of multiple hole burning, hole burning can not overlap, a factor is the spacing of the hole burning, non-homogeneously broadened medium is the longitudinal mode spacing. And at the same time, the rubber finish can make the body of green laser pointer warm.
Another factor is the width of the hole burning. If we burn a hole overlapping the criterion given hole burning FWHM (half-maximum width), only the width than the longitudinal mode spacing is also a large longitudinal mode will produce the hole burning overlap, forming a strong competition. This competition is often constitute one of the reasons that the laser output instability. The width of the hole burning in lasers subject to two effects of the laser gain medium and cavity. In the cavity, the inevitable introduction of loss due to output coupling, the longitudinal mode has a certain width: line width of the media but also by the saturation factors in the laser gain medium: Finally, the width of hole burning to have these two width integrated to set. Therefore, the black rubber finish of green laser pointer is the sweet and considerate design.
Under normal circumstances this will involve convolution calculation, most of the exercises will allow one to simplify a multi-purpose. If the cavity longitudinal mode width is very small, play a major role is the saturation line width of the media, you need to calculate the longitudinal mode of oscillation intensity: and put it into the width of the media above the saturation effect of impact expression calculated. As a result, need to know the saturation intensity, non-homogeneously broadened linewidth, but also need to know how long the size of the loss of the size of the super-pumped threshold, or the small-signal gain per unit length: the gain medium. If the width of the longitudinal mode of the cavity plays a major role on the basis of the width of plus the effect of a saturated medium line width. And the appearance of green laser pointer is very fashionable and attractive.
As a result, the cavity length and reflectivity of output mirror will become the determining factor. The frequency pulling the impact of the longitudinal mode spacing. Deviate from the cavity longitudinal mode frequency of the phenomenon known as frequency pulling effect. Frequency pulling effect of dispersion on the results of the impact of refractive index, relative to the size of the additional phase shift cavity medium is directly determined by the refractive index changes: the total phase shift in the laser cavity has been media we need to meet the resonance condition: the corresponding frequency was likely to form the longitudinal mode frequency of the oscillation. Therefore, the longitudinal mode frequency spacing: Lorentz linear homogeneously broadened media: the longitudinal mode frequency spacing: For non-Gaussian linear homogeneously broadened media. They can use the specific key of   green laser pointer .