To obtain an apparatus for image formation which is stable and has excellent dot reproducibility and high picture quality by making the states of a toner layer and a developer layer on a developing sleeve uniform and to obtain a method and an apparatus for fluidity evaluation which can accurately evaluate the fluidity of a toner or developer.

The surface of the toner layer or developer layer formed on the developing sleeve 6 is irradiated with laser light and the speckle pattern of its reflected or scattered light is measured to evaluate the surface uniformity of the toner layer or developer layer. The apparatus for image formation is characterized in that the laser irradiation power of the laser light is 0.1 to 10 mW and the laser spot diameter is 100 μm to 10 mm. Further, the method and apparatus for fluidity evaluation adopt the above-mentioned evaluation.