rails return json for fullcalendar.js dates displays

gistfile1.rb

# Model
class Meeting < ActiveRecord::Base
  scope :date_range, lambda {|*args| where("start_date between ? and ?", args.first, args.last) }  
end

#Controller
# fullcalendar.js dates displays

    def meeting_dates
      start_range = params[:start].present? ? Time.at(params[:start].to_i) : Date.civil(Time.now.year, Time.now.month, 1)
      end_range = params[:end].present? ? Time.at(params[:end].to_i) : Date.civil(Time.now.year, Time.now.month, -1)
      @meetings = Meeting.date_range(start_range, end_range).by_account(current_account.id)
      
      respond_to do |format|
        format.json { render :json => @meetings}
        format.html
      end
    end