A multi-spectrum based image fusion apparatus, comprising: a light acquisition device, an image processor, a signal controller, and an image sensor having five types of photosensitive channels, the five types of photosensitive channels comprising red, green and blue RGB channels, an infrared IR channel and a full-band W channel; wherein the light acquisition device is configured to acquire target light corresponding to incident light, the acquiring of the target light comprising filtering a spectrum component of a first predetermined wavelength range from the incident light to obtain the target light; wherein the first predetermined wavelength range is a spectrum wavelength range in which a difference between responsivities of the RGB channels and of a brightness channel of the image sensor at an infrared band is greater than a first predetermined threshold, the brightness channel being the IR channel or W channel, and wherein the first predetermined wavelength range is [T1, T2], wherein the value of T1 is in a range of [600 nm, 800 nm], and the value of T2 is in a range of [750 nm, 1100 nm], and the light acquisition device comprises a band-stop filter and an optical lens of a first type; wherein the optical lens of the first type is configured to transmit the incident light to the band-stop filter in a full spectrum transmission manner; and the band-stop filter is configured to filter the spectrum component of the first predetermined wavelength range from the light transmitted from the optical lens of the first type to obtain the target light, or, the light acquisition device comprises an optical lens of a second type, which is capable of filtering the spectrum component of the first predetermined wavelength range; the image sensor is configured to convert the target light into an image signal through the RGB channels, the IR channel and the W channel, wherein during the conversion from the target light into the image signal by the image sensor, in a second predetermined wavelength range of the infrared band, differences between the responsivities of the RGB channels are lower than a second predetermined threshold, wherein the second predetermined wavelength range is [T3, T4], wherein T4 is greater than T3, T3 is greater than or equal to 750 nm, and T4 is less than or equal to 1100 nm; the image processor is configured to analyze the image signal into RGB color signals and a brightness signal, and fuse the RGB color signals and the brightness signal to obtain a fused image, wherein a collection of the channels based on which the RGB color signals and the brightness signal are obtained comprises the five types of photosensitive channels. a light acquisition device, an image processor, a signal controller, and an image sensor having five types of photosensitive channels, the five types of photosensitive channels comprising red, green and blue RGB channels, an infrared IR channel and a full-band W channel; wherein the light acquisition device is configured to acquire target light corresponding to incident light, the acquiring of the target light comprising filtering a spectrum component of a first predetermined wavelength range from the incident light to obtain the target light; wherein the first predetermined wavelength range is a spectrum wavelength range in which a difference between responsivities of the RGB channels and of a brightness channel of the image sensor at an infrared band is greater than a first predetermined threshold, the brightness channel being the IR channel or W channel, and wherein the first predetermined wavelength range is [T1, T2], wherein the value of T1 is in a range of [600 nm, 800 nm], and the value of T2 is in a range of [750 nm, 1100 nm], and the light acquisition device comprises a band-stop filter and an optical lens of a first type; wherein the optical lens of the first type is configured to transmit the incident light to the band-stop filter in a full spectrum transmission manner; and the band-stop filter is configured to filter the spectrum component of the first predetermined wavelength range from the light transmitted from the optical lens of the first type to obtain the target light, or, the light acquisition device comprises an optical lens of a second type, which is capable of filtering the spectrum component of the first predetermined wavelength range; the image sensor is configured to convert the target light into an image signal through the RGB channels, the IR channel and the W channel, wherein during the conversion from the target light into the image signal by the image sensor, in a second predetermined wavelength range of the infrared band, differences between the responsivities of the RGB channels are lower than a second predetermined threshold, wherein the second predetermined wavelength range is [T3, T4], wherein T4 is greater than T3, T3 is greater than or equal to 750 nm, and T4 is less than or equal to 1100 nm; the image processor is configured to analyze the image signal into RGB color signals and a brightness signal, and fuse the RGB color signals and the brightness signal to obtain a fused image, wherein a collection of the channels based on which the RGB color signals and the brightness signal are obtained comprises the five types of photosensitive channels.